Conventional ACs and making them useful

[massey]

I've always liked autocannons.  I know they're overweight and underpowered, the couch potato of the Battletech weapons list.  But I like them anyway.  So I've been thinking of ways to make ACs competitive, without having to change weight or crit slots.

Several types of specialty ammo should be combined together, and should come as standard with no reduction of ammo capacity.  Autocannons may not shine against Battlemechs, but they'd be effective against multiple units.  You take an AC-5 instead of a large laser because of the cool ammo effects.

I propose that standard AC rounds (including those fired by Ultras and LB-Xs) inflict their standard damage against infantry, with no reduction.  They are explosive bursts, after all.  An AC-5 does 5 points of damage to infantry (double if they are in a clear hex), an AC-10 does 10 points, etc.  They also get the benefits (but not the penalties) of flak ammo.  Autocannons receive a -2 to hit modifier against VTOLs and fighters.  Tracer rounds are optional -- it's easier for you to see them at night, but also easier for them to see you.  No reduction in damage for taking tracer ammo.

I think these changes would make ACs understandable.  It wouldn't feel like a waste if you saw those weapons on a vehicle or mech.  Even if your fights are mech vs mech only, you'd at least understand why the designer chose to put that gun on your mech.

[Retry]

I'm getting a sense of deja vu...

I propose that standard AC rounds (including those fired by Ultras and LB-Xs) inflict their standard damage against infantry, with no reduction.  They are explosive bursts, after all.

Well, I definitely understand that explanation.  However, that's essentially what the SRMs and LRMs are, big explosive cylinders, so a case could be made that those would be able to do the same thing.

They also get the benefits (but not the penalties) of flak ammo.  Autocannons receive a -2 to hit modifier against VTOLs and fighters.

Do Ultras and LB-Xs using solid shot also get the flak bonus?

I think these changes would make ACs understandable.  It wouldn't feel like a waste if you saw those weapons on a vehicle or mech.  Even if your fights are mech vs mech only, you'd at least understand why the designer chose to put that gun on your mech.

Essentially, this solution is to combine a few ammo types and call the Autocannon an all-in-one utility weapon.  It's an interesting idea, but it's already basically a utility weapon as long as you have the ammo bays (like the Hetzer with 5 tons for 1 AC/10, plenty for special ammo).  So what it really does is make AC designs that don't have deep bays into all-in-one, and the other AC designs with deep ammo bays just kind of don't benefit.

But I prefer the idea that if you want to fully use the flexibility of alternative ammunition (ACs, LRMs, SRMs...), then you should invest in deeper ammo bins.  It's a decent idea to enhance the autocannon, but I think it's not the best one.

Is this thread for this idea specifically, or is it a kind of open discussion to improving the Autocannon?  If it's the latter, I'd be happy to add the fixes I applied to the AC to make them competitive w/o touching weight or crit slots.

[Cannonshop]

Huh, Autocannons are actually pretty frikking useful as they are.  esp. in the absence of double-heat-sinks, or properly employed with the variant ammo types in the presence of DHS.  I think maybe people make the mistake of wanting everything direct-fire to be an all-turns-alpha-baby.

[Daryk]

I wouldn't assume all ACs use "explosive" ammunition.  Kinetic penetrators now are pretty much just tungsten rods propelled at ridiculous speeds.

[Retry]

I wouldn't assume all ACs use "explosive" ammunition.  Kinetic penetrators now are pretty much just tungsten rods propelled at ridiculous speeds.

Real-life kinetic penetrators do that, but BT autocannons defeat battlemechs by ablating the armor and then battering the internals to death.

For what it's worth, TechManual pg 207 has this to say about BT autocannons:

...most autocannons deliver their damage by firing high-speed streams or bursts of high-explosive, armor-defeating shells through one or more barrels.

That would imply that much of the autocannon's damage is chemical (explosive-based), and not kinetic.


One big issue is that the ACs are almost always easily replaced with a combination of energy weapons, LRMs, and SRMs for an overall more effective weapon system, even in circumstances that should be favorable to the ACs (The Single Heat Sink era and on Vehicles).

The Scorpion light tank has the AC/5.  Make it a missile tank with 2 LRM-5s (2 tons ammo) and 2 SRM-2s (1 ton ammo).  The resultant vehicle has a longer range, slightly improved battlefield endurance, and greater average damage across all range brackets with a possible exception of hexes 4-6, but the to-hit numbers need to be abysmal for the AC/5 to come out on top there.

The Partisan heavy tank has a quad AC/5 battery and 2 tons of ammo.  Since it's an ICE tank, the AC/5 has advantages over energy weapons such as not having to pay for heat sinks or power amplifiers.  Despite those advantages, swapping the 4 AC/5s + ammo with 2 PPCs is easily done and gets a spare half-ton for armor or something, and the resulting PPC Partisan is cheaper than the original (C-Bills).

The Annihilator battlemech has 4 AC/10s and 4 medium lasers as backup, but only has the heat sinks to fire 6 of the weapons consistently (or 5 if walking/running).  The AC ammo is basically at the bare minimum with 10 turns of firing time.  Replace everything with 5 Large Lasers and the sinks to fire them non-stop (and maybe a token flamer), and you can fire forever with no ammo worries or explodey bits, a metric tonne of crit padding, and around 50% extra armor, while only sacrificing some damage at short range.  Of course, the new Annihilaser is a bit boring, but it's also effective (as much as a 2/3 mech can be, anyways).

The AC/5 and (to a somewhat lesser extent) the AC/10 suffer from this easy-replacement syndrome the most.  So the only roles that are somewhat unique to vanilla Autocannons is the AC/2's range, the AC/20's damage concentration, and alternative ammo.  But every single one of those has a big asterisk.

AC/2s are the undisputed king of range in Intro-tech, and only LRMs get close to them.  The damage is low, but annoying people to death is an exploitable niche.  Some designs like the Warrior make good use of it, other designs like the Dragon DRG-1C do not.  The asterisk here is that post-introtech, lots of weapons encroach its niche by having similarly long ranges while having more balanced firepower (ERPPC, Gauss Rifle, Light Gauss Rifle).  The ELRM is prototyped in 3054 and becomes common by 3083, and does the niche of "super long range bee-stings" better.

AC/20s have that huge, scary 20-point punch of doom.  How useful that is vs just mounting a ton of medium lasers and melting armor through brute force is somewhat dependent on your opinion.  Still, it's a niche that's unchallenged in 3025.  The asterisk here is that post-introtech, there's a lot of weapons that challenge the AC/20 in the massive hole punch role, including the Gauss Heavy Gauss type weapons, the Thunderbolt-15 and -20 missiles, and the Heavy PPC, so there's plenty of options that gets you a similar scary punch (and sometimes even more damage) but with better range brackets and thus higher usability.

So the last niche is alternative ammo.  Not available in intro-tech but there are some useful options (Precision, Flak, Flechette if your ammo bay is deep) and some less-useful options (Tracer).  The asterisk here is that despite their low-tech nature the alternative ammo options are actually rather rare in-universe.  For instance, Flak ammo has an availability rating of E-F-F-E, so it's tricky to get during the Star League and becomes near impossible to find during the Succession Wars and the Clan Invasion.  Even if you have a few Partisans, chances are you won't be able to get enough Flak to make the most of it (unless you handwave the silliness of the idea that flak is super rare, but then you're basically playing in an AU).  By the time the other alternative ammo like Precision becomes more available, the vanilla ACs are obsolescent by Inner Sphere standards anyways.  In contrast, IS LRMs and SRMs, which have somewhat better utility with their alternative ammunition (Inferno, Mine-laying and Smoke all come to mind) still compare favorably even as Lostech becomes available again.

[RifleMech]

I think ACs are useful, especially on lower tech units. I think it would be nice if there were more ammo types and that Ultras and LB-X could use them. It'd also be nice if Ammo weren't limited to being reduced by half. Why not a third or a quarter depending on the ammo type? I also wonder about rounds having their damage and their range changed depending on the ammo.

Like a double load round having the range reduced (short is medium, medium is long, long is extreme). (roll on cluster chart) and has a third fewer shots. Paint rounds though could have 25% more ammo. or something.

I would also check with TPTB about the availability of ammo types for AC/s. They're far more rare than they should be.

As for other weapons being "better" can we please not go there. It's off topic and doesn't help improve AC/s any.


As for infantry, I'd roll on the cluster hit chart since AC/s are firing bursts.

[garhkal]

If one did see a 'shift over' for AC ammo to be one of the specialty types at the base (so as to not get 1/2 ammo per ton), i'd probably see it all shifting to LB ammo..  And maybe convert all slug ammo to being precision or AP.

[Hptm. Streiger]

 Don't ask for general approval, if you think a change works for you use it.
There will hardly a general consensus.
For example the mentioned partisan 4 ac5s vs 2 ppcs some like to have 4 chances to do some damage over two chances.

Anyhow I would consider the ammunition load as an issue, 10-12 rounds are more than enough for most CBT games. So alternate range/damage/heat to decrease the shots per ton.
Even for SRM2, 4s and LRM5s

Or increase the front loading effect by increasing the shots fired per round.... no cluster rules, just roll 3 times for SRM2 and AC2, 2 times for SRM4, LRM5 and Ac5

[RifleMech]

I know most think 10-12 rounds is good but I tend to thing about campaigns, and not single battles. That's what I was thinking ammo should increase or decrease by more than just -50% or x2 the amounts.

I also think it'd be interesting to have the ranges and maybe even the heat and damages change.

For example,
AC/5 low powered round
Heat 1, Range -1 range band, Damage same with the modified range, 3 at normal ranges, Ammo 25 rounds.
AC/5 high powered round
Heat 3, Range +1 range band, Damage 8 at modified range, normal past that. Ammo 15 rounds.

[Atarlost]

There are three problems: the AC-5 before precision ammo, the LAC-2, and wet stowage being invented in the 2450s instead of the 1940s in the Battletech universe. 

The AC-5 being bad has been done to death, but once precision ammo comes on the scene it starts looking pretty good even on mechs.  You run out of crits pretty fast trying to use large X-pulse lasers and you're still not matching the AC-5's range.  Nothing reaches out and touches annoying hovercraft like an AC-5 with precision ammo. 

The LAC-2 is half the weight of an AC-5 doing less than half the damage with admittedly no minimum range, but it's not looking good.  It might still be better than X-pulse lasers, but the AC-5, being also an autocannon with the same ammo options, does pretty much everything better and is older, more common tech. 

And the ammo thing is obvious.  Without CASE II ammo explosions are crippling even if CASE makes them not lethal except to XLFE mechs.  That effects missiles too.  It's hard to justify an ammo weapon that isn't doing something uniquely valuable with the current explosion rules.  It'd be a lot easier to justify taking ammo into battle if everything had free CASE in every location and CASEd stuff had half weight CASE II. 

A 20% ammo capacity increase so that all autocannon ammo bins are divisible by 2 would be nice as well it double size rounds are going to continue to be a thing. 

[RifleMech]

The LAC-2 is good for units that can't mount a larger AC and still want to reach out to 18 hexes.

Era Report:2750 mentions an early type of CASE that wasn't compatible with modern armors and need for sealing systems. It's use of blow away panels though sounds just like CASE though. :-\

One thought I've had, off and one, was being able to fire single rounds at half damage and ammo usage. So you could select from single rounds, standard burst, or rapid-fire burst.

[theagent]

The thing that's been bugging me more & more in the whole "autocannons suck, energy weapons rule!" debate is that everything is working off of the "they're an island unto themselves".  That is, when people look at the weapons (damage, slots, tonnage, etc.), they only consider the weapons themselves...& not the heat they're generating.

For combat vehicles & conventional fighters, that's not an issue -- at least not for autocannons & missiles -- because neither a CF nor a CV has to track the heat from those weapons.  But boy, you'd better make sure you have the heat sinks for an energy weapon, especially for an ICE-powered unit.

Even on BattleMechs & other units that track heat for every weapon, though, it's as if everyone ignores that particular aspect of it.  "Well, I've already decided how many heat sinks I'm going to have on it, so I'll just load up a ton of MLs & other energy weapons anyway to maximize my tonnage".  That kind of attitude, though, gets you the Clan Nova Prime.  Yes, 12 Clan EMLs are a nasty weapons load to face...but if the Clanner jumps & Alpha Strikes, he's sitting at 29 heat (with a good chance of being shut down for a turn).  If she manages to maintain fire discipline, she can fire 7 of those on 1 turn (still a nasty combo) & only go up 4 on the scale, but then she's limited to only firing 6 of them for 4 straight turns before hitting 0 on the scale.  That means those unfired 6 EMLs are at best "backup" weapons; at worst, they're wasted tonnage.

"But wait!"(you say), "BattleMechs come with free heat sinks anyway, so you don't have to worry about those first ones!"  Well, that's partially correct.  Sure, you can take those heat sinks into account for comparisons, but you have certain issues.  But which weapon do you pick first to use those "free" heat sinks:  the weapon that uses the most heat?  highest BV?  highest max damage?  longest range?  That can make a big difference.  And trying to compare based on a specific design or model gets deep into the weeds, given the myriad of configurations out there.

Which is why, when I usually compare the different weapons, I consider both how much ammo the ballistic & missile weapons need to meet 'legal' design requirements (i.e. 10 shots/salvos, 20 for Ultras, etc.), & how many extra tons/slots they need for the heat sinks needed to fire them.  I also look at how you can pair up some of the ammo-dependent weapons, particularly the ones with more than 10 shots/salvos per ton of ammo.

Example 1:  the "horrible" AC/5 vs. the PPC.  Both weapons happen to be installed on the BNC-3C Banshee, & both have the same range envelope, so they're fairly easy to compare.  The standard comparison would say the AC/5 is weak compared to the PPC because it's "heavier" & "takes up more space".  Once you factor in the heat sinks, though, it becomes quite a different story.  A PPC generates 10 heat, so it needs 10 heat sinks added on.  That raises its tonnage to 17 (7 tons PPC + 10 tons SHS) & its slots to 13 (3 PPC + 10 SHS).  The AC/5, however, requires 10 tons (8 tons AC + 1 ton SHS + 1 ton ammo) & 6 slots (4 AC + 1 SHS + 1 ammo).  So, the AC/5 takes up 59% of the tonnage & 46% of the slots of a PPC, while dealing half the damage. Since that ton of ammo provided 20 shots, however, we can also evaluate a "double AC" installation with 2 AC/5s.  That takes up 19 tons (16 tons ACs + 2 tons SHS + 1 ton ammo) & 11 slots (8 AC + 2 SHS + 1 ammo).  In this case, it takes 112% of the tonnage & 85% of the slots for twin AC/5s to deal the same damage as a PPC.

Example 2:  the AC/10 & Large Laser also share a range envelope.  The latter needs 13 tons (5 tons LL + 8 tons SHS) & 10 slots (2 LL + 8 SHS).  The AC/10 needs 16 tons (12 tons AC + 3 tons SHS + 1 ton ammo) & 11 slots (7 AC + 3 SHS + 1 ammo).  So the AC/10 takes up 23% more tons & 10% more slots, but provides 25% more damage.

[RifleMech]

I know I take into account, heat and unit type. I know some do ride the heat curve and it can be a useful tactic but that curve depends on the unit and engine type. Vehicles need to be heat neutral and Combat Vehicles can change engines to gain free heat sinks. A Support Vehicle can't. Their engines don't come with free heat sinks, regardless of the engine type. Also a Mech with a ICE is going to have a much lower heat curve than a mech with a SFE and DHS.

[Atarlost]

The LAC-2 is good for units that can't mount a larger AC and still want to reach out to 18 hexes.

The catch is that in its era you're looking at freezers and if you can't mount an AC-5 you also aren't mounting enough stuff to use up your free sinks, which makes energy weapons a lot more efficient.  The precision bonus is nice, but you could have an ERLL doing four times as much damage and that's probably better in most cases. 

The thing that's been bugging me more & more in the whole "autocannons suck, energy weapons rule!" debate is that everything is working off of the "they're an island unto themselves".  That is, when people look at the weapons (damage, slots, tonnage, etc.), they only consider the weapons themselves...& not the heat they're generating.

And you're ignoring four important factors:

First, the difference between having an ammo bin crit and having a heatsink crit.  Losing a heatsink loses you 10% of a PPC.  You can fire it a little less often or if you're playing TacOps even tune the damage down to 9.  Having lots of heatsinks means having lots of chances for a crit to have only minor effect.  Having an ammo bin crit destroys your mech unless you add CASE in which it destroys a hit location.  Even if you have CASE II it's another crit chance and you're out the ammo you need to fire your autocannons at all. 

Second, bracket firing.  It's not uncommon to have PPCs or LRMs or even large lasers share heatsinks with medium lasers.  Sometimes LRMs share heatsinks with large lasers.  If you demand ice cold alpha babies you artificially penalize energy weapons and missiles, which makes autocannons look better than they actually are. 

Third, endurance.  If you have 10 shots you have to worry about running out of ammo and can't take low odds shots and you miss 100% of the shots you don't take.  The usual rule of thumb is 12-15 shots minimum.  Mechs with 10 shots exist, but they tend to be derided for their tiny ammo bins.  That's not really hurting the AC-2 unless you want to quad mount them, but it makes your AC-5 and AC-10 comparisons less advantageous. 

Fourth, crits don't matter unless freezers are in play and freezers change the tonnage dynamic drastically in favor of energy weapons.  Freezers come in before other techs that trade crits for weight and only assault weight quads are in danger of running out of crits before advanced tech. 

All of these mean that near ties go to the energy weapon.  LBX-s do a unique and useful thing and I don't think anyone rags on them, and gauss rifles do an almost unique and useful thing and nobody passes on a gauss rifle except in clantech where the thing they do isn't unique.  Crit compactness sometimes comes up in their era, but they aren't relying on crit compactness to be useful. 

So let's look at your Banshee.  This is almost a strawman, but you brought it up.  The Banshee has 16 heatsinks.  Pull the AC-5 for a PPC and 2 heatsinks and it'll have 18 heatsinks and be able to fire the second PPC between 2 rounds in 3 and 1 round in 2 depending on movement for the same or better damage over time.  To make an AC-5 look good on a mech you have to have exactly the right amount of tonnage to play with and no slack in your heat budget.  If you're a little bit overcooled (or equivalently have a couple tons too much to play with) the PPC is better.  If you're undercooled you can often get more from an AC-2 and two heatsinks.  AC-10s have a little more leeway because there are a lot of heads and rear torsos with 8 or 9 armor on them, but it's still not something you should see in a blank sheet mech design given the alternatives of "shave off 5 tons and use a large laser" or "add 5 tons and use a PPC with a couple MLs."

AC-5s specifically also get impinged on by missiles.  You can have an LRM-10 with 12 shots and an SRM-4 with 25 shots for the weight of an AC-5 with 20 shots.  The AC-5 produces less heat on a mech, but this denies the AC-5 the niche the AC-10 excels at as a main gun for tanks.  I think that's the real reason the AC-5 gets so much more hate than the AC-10.  People look at the Po and Zhukov and say "I approve of the decision to use an AC-10 here," or at the Goblin and say "why doesn't this have an AC-10?" but people look at the Scorpion and say "why would I ever not use this LRM variant?" and the Vedette and say "why doesn't this have a LRM variant like the Scorpion?".  Thus, they have a better general impression of the AC-10 and are more forgiving of it being used less than ideally. 

[Retry]

If a weapon that's lightweight and reaches at least 18 hexes is your design criteria, the LPPC, Mech Mortar 1, LRM-5, MML-3, MML-5, Thunderbolt-5, and NLRM-5 all accomplish the goal for less weight.  All but the LPPC has a lower up-front cost.  Most of them are more effective weapon systems in-general (MMLs, LPPC, NLRMs).  Some have a tech level that is the same (MML-3, -5) or even lower (LRM-5, MM-1) and are thus easier to maintain on the field.

The thing that's been bugging me more & more in the whole "autocannons suck, energy weapons rule!" debate is that everything is working off of the "they're an island unto themselves".  That is, when people look at the weapons (damage, slots, tonnage, etc.), they only consider the weapons themselves...& not the heat they're generating.

...No?

When I said "The Partisan can replace the AC5s with PPCs and become cheaper", "The Annihilator can replace the AC10s with LLs and be as effective with a massive armor bonus", and other such examples, I was in fact considering the weapon systems as a whole: With all those necessary accessories like ammunition, heat sinks, and power amplifiers.

I'm not too interested in going through yet another 10 pages of arguing about the ACs, so hopefully this can be kept brief.

Even on BattleMechs & other units that track heat for every weapon, though, it's as if everyone ignores that particular aspect of it.  "Well, I've already decided how many heat sinks I'm going to have on it, so I'll just load up a ton of MLs & other energy weapons anyway to maximize my tonnage".  That kind of attitude, though, gets you the Clan Nova Prime.  Yes, 12 Clan EMLs are a nasty weapons load to face...but if the Clanner jumps & Alpha Strikes, he's sitting at 29 heat (with a good chance of being shut down for a turn).  If she manages to maintain fire discipline, she can fire 7 of those on 1 turn (still a nasty combo) & only go up 4 on the scale, but then she's limited to only firing 6 of them for 4 straight turns before hitting 0 on the scale.  That means those unfired 6 EMLs are at best "backup" weapons; at worst, they're wasted tonnage.

I agree that the Clan Nova Prime is a poor design.  Poor designs are not unique to energy weapons (see any design with those so-called "torso bombs").  That machine's flaws is particularly easy to fix: Throw out 4 of the lasers for heat sinks for continuous firing.  The new machine is actually more useful and BV goes down by nearly 400 points. (C-Bills also sees a slight discount)

This seems like a bit of a side-show though.  I don't really see how a bad design that happens to use energy weapons is a point in favor of the autocannon.

"But wait!"(you say), "BattleMechs come with free heat sinks anyway, so you don't have to worry about those first ones!"  Well, that's partially correct.  Sure, you can take those heat sinks into account for comparisons, but you have certain issues.  But which weapon do you pick first to use those "free" heat sinks:  the weapon that uses the most heat?  highest BV?  highest max damage?  longest range?  That can make a big difference.  And trying to compare based on a specific design or model gets deep into the weeds, given the myriad of configurations out there.

Which is why, when I usually compare the different weapons, I consider both how much ammo the ballistic & missile weapons need to meet 'legal' design requirements (i.e. 10 shots/salvos, 20 for Ultras, etc.), & how many extra tons/slots they need for the heat sinks needed to fire them.  I also look at how you can pair up some of the ammo-dependent weapons, particularly the ones with more than 10 shots/salvos per ton of ammo.

We're in agreement here.  When doing a comparison between the two, I generally go for "worst case" or "near worst case" scenarios where the new weapon needs to arrive fully sinked.

Example 1:  the "horrible" AC/5 vs. the PPC.  Both weapons happen to be installed on the BNC-3C Banshee, & both have the same range envelope, so they're fairly easy to compare.  The standard comparison would say the AC/5 is weak compared to the PPC because it's "heavier" & "takes up more space".  Once you factor in the heat sinks, though, it becomes quite a different story.  A PPC generates 10 heat, so it needs 10 heat sinks added on.  That raises its tonnage to 17 (7 tons PPC + 10 tons SHS) & its slots to 13 (3 PPC + 10 SHS).  The AC/5, however, requires 10 tons (8 tons AC + 1 ton SHS + 1 ton ammo) & 6 slots (4 AC + 1 SHS + 1 ammo).  So, the AC/5 takes up 59% of the tonnage & 46% of the slots of a PPC, while dealing half the damage. Since that ton of ammo provided 20 shots, however, we can also evaluate a "double AC" installation with 2 AC/5s.  That takes up 19 tons (16 tons ACs + 2 tons SHS + 1 ton ammo) & 11 slots (8 AC + 2 SHS + 1 ammo).  In this case, it takes 112% of the tonnage & 85% of the slots for twin AC/5s to deal the same damage as a PPC.

We're looking at the same data and coming to two fundamentally different conclusions.  While you think this shows that the AC/5 is not so bad after all, I'm seeing my position verified.

Since I do a lot of things with campaigns, I'll put it another way.

Let's say I'm some sort of big wig who manages the supplies and military hardware of my nation-state, Chief quartermaster or whatever.  A significant proportion of my supply line consists of logistical support for the AC/5; not just the ammunition but the infrastructure such as the supply dumps and ammunition trucks necessary to keep the autocannons stocked in the field.

A weapons manufacturing company with a new weapon in the works has requested a meeting with me to discuss the future of my nation-state's next-generation military hardware.  IOW, he's selling his product to me.  He's aiming to overthrow the AC/5's niche so he can sell his weapon and presents the following bullet-points in favour of it:

• Almost every 2 instance of the AC/5 can be replaced with the new weapon for equivalent effectiveness (range & overall damage).
   Applies vehicles like the Pike AC5 and the Partisan, as well as mechs like the Cataphract 4X and Emperor 5A
• Certain existing single-AC/5 designs may still be capable of accepting a PPC + some heat sinks as a replacement and come out ahead as an overall weapon system.  (Hunchback 4N, Sentinel 3K, Shadow Hawks, Wolverine 6R all come to mind)
• Replacing the two AC/5 weapon system in this fashion will reduce the effective weapon system's weight by 2 tons or more (depending on the original's ammo load)
• Replacing the two AC/5 weapon system in this fashion will reduce the up-front C-Bill cost of next-generation battlemechs
• Replacing the two AC/5 weapon system in this fashion will reduce the operational cost of the next-generation battlemechs since the new weapon uses fuel as "ammunition".
• Replacing the two AC/5 weapon system in this fashion will reduce the size of the infrastructure required to support the machine, reducing costs and weight of the logistical elements the Dropships must carry to support the vehicles on the ground.
• Replacing the two AC/5 weapon system in this fashion will effectively make the unit's combat endurance indefinite regardless of the original AC/5 system's ammo load (especially fusion engines, no magazines to deplete)
• Replacing the two AC/5 weapon system in this fashion will reduce downtime due to Re-arming (see above)
• In the event of critical damage, the next-gen mechs with the new equipment is significantly more likely to take much less devastating damage than the AC/5 platform.  (Single heat sinks act as "crit soaks" and only reduce dissipation by -1.  The AC/5s are far more likely to get a weapon hit or even an ammunition detonation.)

The "next-generation" weapon in question is the humble Inner Sphere PPC.

Every single one of those claims are true.

I'm the Quartermaster.  From my perspective at the national grand strategy scale, there's a verifiable avalanche of benefits of replacing 2 AC/5s with an equivalent PPC system whenever possible.  Reduced acquisition cost.  Reduced operational cost.  Reduced logistical footprint (which results in reduced transportation cost).

The commanders on the ground managing campaigns also have significant benefits going Energy here.  Their mechs have less down-time as they don't have to spend extra time re-arming their AC/5s (this applies even if they mount other ammo-dependent weapons), their warships and dropships have to dedicate less weight to ammunition.

From the perspective of the individual mechwarrior in the cockpit, the PPC's performance is very similar to two AC/5s, but it weighs a tad less on a Battlemech, won't run out of ammo, and it won't explode on you as long as you don't do anything stupid.

So why shouldn't I, the Quartermaster, have our next-generation Battlemechs use PPCs in place of 2 AC5s whenever feasible?  Heck, why shouldn't I refit much of our current AC/5 platforms with PPCs and throw the spare autocannons to the Infantry garrisons as field guns?  Maybe if I had a sizable stock in autocannon manufacturers and loved money more than country...

I mean, what's the AC5 manufacturer's play here?  "If you ignore all the logistical and fiscal advantages of the PPC, two AC/5s are almost as good!"

Okay, that's too silly.  But it's not far from the truth.  Despite the appearance I'm not here just to dunk on the ACs, so I'll give some advantages.

• AC/5s can be field guns.
  That's a solid advantage.  There's not too much competition in its range bracket as a field gun until Ultras, LB-Xs and Gauss come out.
   Still, being a decent field gun is of little consolation to Battlemechs and Vehicles fielding the weapon.
• AC/5s are tech level C, slightly easier to maintain.
  This is true, but the regular PPC is only tech level D, same as Standard Armor, fusion engines, and a whole slew of standard Battlemech components (Gyros, structure, jump jets, heat sinks...).  If you can maintain those, you can maintain the PPC.
• Alternative Ammo
  It's an advantage... if you can get them.  The availability of non-standard ammunition is rather poor in most eras despite their simplicity for some reason (Flak ammo is F during the succession wars?!).  Their ammunition types are not quite as interesting as LRM's unfortunately.  Precision is almost always useful, and AP can have its moments, but both are high-tech (yes, more advanced than the PPC), low-availability, and are introduced during the Clan Invasion.  At that point there's a whole lot more options than the vanilla Autocannons.
• It's sometimes more space efficient.
  As your calculations show, the 2 AC/5s have a bit less crit space for the same amount of damage.  Sometimes an AC/5 system might be able to just fit when a PPC system would not.  However, this doesn't apply in 3025: you need those fancy DHS, Endo-Steel, or Ferro-Fibrous armors to actually hit that crit cap.  It's also somewhat of a mixed blessing, as there's less "crit sponges" and proportionately more high-value crits on the AC configuration (Weapon and ammo).  This advantage is further offset if you want to add more ammo (either for special munition use or just so you don't run out during a campaign) or CASE/CASE II.
• It's not a PPC
  I'm serious.  That's an advantage.  PPCs are an energy weapon, so they deal half damage to Reflective Armor.  PPCs are also PPCs (obviously), so they also deal half damage to active Blue Shield Particle Field Dampers.  Of course, both of those are rather rare.  The former because that armor simply melts in the face of artillery weapons and certain ammunition, and the latter because the PFD is rather over-specialized for PPCs, bulky, heavy, unreliable after a minute of operation, and prone to exploding...
  Hey, I never said it was a good advantage!
• It's an Autocannon
  Yep.  It's an advantage.  Autocannons are cool.
  _{I just wish they were good too...}

Do note when I say something like "Autocannons are not useful" or "Autocannons suck", I don't mean in the sense that it is interchangeable with some squirt gun.  Any Battlemech-scale weapon is very much capable of flattening puny humans or knocking down an Atlas given enough time and luck, and such weapons need respect from Mechwarriors in the sense that they can kill you.

But, they are not necessarily useful in the sense in the sense that "This weapon is highly effective and good in its niche, and I don't feel I would gain much if I were to pick an alternative loadout for my 'Mech or vehicle fleet."  That just isn't there.  That's why this topic was posted, and why variants of that topic keep getting posted over and over.

[RifleMech]

The catch is that in its era you're looking at freezers and if you can't mount an AC-5 you also aren't mounting enough stuff to use up your free sinks, which makes energy weapons a lot more efficient.  The precision bonus is nice, but you could have an ERLL doing four times as much damage and that's probably better in most cases. 

That depends on the unit though. There are units that can't mount DHSs.

And you're ignoring four important factors:

First, the difference between having an ammo bin crit and having a heatsink crit.  Losing a heatsink loses you 10% of a PPC.  You can fire it a little less often or if you're playing TacOps even tune the damage down to 9.  Having lots of heatsinks means having lots of chances for a crit to have only minor effect.  Having an ammo bin crit destroys your mech unless you add CASE in which it destroys a hit location.  Even if you have CASE II it's another crit chance and you're out the ammo you need to fire your autocannons at all. 

Ammo explosions are always a problem but so is being shutdwn do to heat.

Second, bracket firing.  It's not uncommon to have PPCs or LRMs or even large lasers share heatsinks with medium lasers.  Sometimes LRMs share heatsinks with large lasers.  If you demand ice cold alpha babies you artificially penalize energy weapons and missiles, which makes autocannons look better than they actually are. 

True that does happen and can be effective. On the other hand though you've got weapons you can only use half the time.

Third, endurance.  If you have 10 shots you have to worry about running out of ammo and can't take low odds shots and you miss 100% of the shots you don't take.  The usual rule of thumb is 12-15 shots minimum.  Mechs with 10 shots exist, but they tend to be derided for their tiny ammo bins.  That's not really hurting the AC-2 unless you want to quad mount them, but it makes your AC-5 and AC-10 comparisons less advantageous. 

Ammo endurance is usually a problem however, those with few shots are usually weapons you don't want to get hit by.

Fourth, crits don't matter unless freezers are in play and freezers change the tonnage dynamic drastically in favor of energy weapons.  Freezers come in before other techs that trade crits for weight and only assault weight quads are in danger of running out of crits before advanced tech. 

Actually, crits are a problem for all mechs. FF takes 14 crits, HFF takes 21, ES 14 crits, XL Engine 6 crits, XXL 12 crits, XL gyro another 2,  and the smaller the engine is the fewer heat sinks it holds. And each DHS is 3 crits for IS versions.

All of these mean that near ties go to the energy weapon.  LBX-s do a unique and useful thing and I don't think anyone rags on them, and gauss rifles do an almost unique and useful thing and nobody passes on a gauss rifle except in clantech where the thing they do isn't unique.  Crit compactness sometimes comes up in their era, but they aren't relying on crit compactness to be useful. 

So let's look at your Banshee.  This is almost a strawman, but you brought it up.  The Banshee has 16 heatsinks.  Pull the AC-5 for a PPC and 2 heatsinks and it'll have 18 heatsinks and be able to fire the second PPC between 2 rounds in 3 and 1 round in 2 depending on movement for the same or better damage over time.  To make an AC-5 look good on a mech you have to have exactly the right amount of tonnage to play with and no slack in your heat budget.  If you're a little bit overcooled (or equivalently have a couple tons too much to play with) the PPC is better.  If you're undercooled you can often get more from an AC-2 and two heatsinks.  AC-10s have a little more leeway because there are a lot of heads and rear torsos with 8 or 9 armor on them, but it's still not something you should see in a blank sheet mech design given the alternatives of "shave off 5 tons and use a large laser" or "add 5 tons and use a PPC with a couple MLs."

That works though because the Banshee uses a fusion engine. With a different engine you get a different number of free heat sinks. That means you'd pay more for heat with energy weapons that you would with autocannons.

AC-5s specifically also get impinged on by missiles.  You can have an LRM-10 with 12 shots and an SRM-4 with 25 shots for the weight of an AC-5 with 20 shots.  The AC-5 produces less heat on a mech, but this denies the AC-5 the niche the AC-10 excels at as a main gun for tanks.  I think that's the real reason the AC-5 gets so much more hate than the AC-10.  People look at the Po and Zhukov and say "I approve of the decision to use an AC-10 here," or at the Goblin and say "why doesn't this have an AC-10?" but people look at the Scorpion and say "why would I ever not use this LRM variant?" and the Vedette and say "why doesn't this have a LRM variant like the Scorpion?".  Thus, they have a better general impression of the AC-10 and are more forgiving of it being used less than ideally.

Missiles are good but they're not sure things. Their damage isn't consistent unless mounted on an AS unit and then they do 6 damage. Hardly better than the AC/5 but with far more expensive ammo. Some also like the increased range the AC/5 has over the AC/10. Also weight is a factor. I can't see a Scorpion mounting an AC/10.

I'm not going to say that AC/5s are the best weapons but they do have have uses. I also think rule changes have hurt the AC/5, and ACs in general more than any other weapon type. All heat sinks used to take crits so having to add add another 10 crits of HS could be a problem. That gave an advantage to cooler running ACs. Now you can get 16 or more DHS in the engine. That's a huge advantage to energy weapons.

If a weapon that's lightweight and reaches at least 18 hexes is your design criteria, the LPPC, Mech Mortar 1, LRM-5, MML-3, MML-5, Thunderbolt-5, and NLRM-5 all accomplish the goal for less weight.  All but the LPPC has a lower up-front cost.  Most of them are more effective weapon systems in-general (MMLs, LPPC, NLRMs).  Some have a tech level that is the same (MML-3, -5) or even lower (LRM-5, MM-1) and are thus easier to maintain on the field.

(snip)

But, they are not necessarily useful in the sense in the sense that "This weapon is highly effective and good in its niche, and I don't feel I would gain much if I were to pick an alternative loadout for my 'Mech or vehicle fleet."  That just isn't there.  That's why this topic was posted, and why variants of that topic keep getting posted over and over.

I also hope this doesn't get into an argument that goes on for 10+ pages.

I do agree that there are weapons that are better than the AC/5, especially newer weapons being used by more advanced units. However, they're not available in all eras. Some are also more difficult to maintain as the have higher tech ratings. That means paying for better techs which increases costs. They also may be harder to replace do to availability. That could mean a unit being stuck in the hanger a while so I'm not sure they end up cheaper in the end.

Again, I don't think AC/5s are the best weapon but they do have uses. And sometimes they might even be the preferred if not the best choice. It depends on a whole lot of factors. I also wouldn't consider replacing 2 weapons for 1 a good choice in all situations. If one is damaged the other can still fire. Repairing and/or replacing them can also be a problem depending on Tech Rating, Tech Skill, Availability, and Cost. X Energy Weapon may have a lesser purchase price but what of the delivery costs? It could be cheaper to buy an Autocannon locally than import PPCs. It all depends on a lot of things.



It still surprises me that the Clans didn't use Improved versions to replace the old Standard versions in their territories and that the Sharks/Foxes weren't selling them on the open market.

[theagent]

The only reason that a PPC-equipped Partisan (3025/3039 variant) "saves" on weight is because it has a 1.5 ton turret instead of the standard version's 3.5 ton turret...& because of the 2 tons of power amplifiers and 20 heat sinks it needs, the overall effect is you have an extra half-ton to play with... enough to either double your MG ammo or add 8 points of extra armor protection on.  But since you still have that half-ton of MG ammo in it, you're just as likely to become a smoking crater with an ammunition hit.  There is also the issue, however, where you are now more vulnerable to weapon critical hits.  On a standard Partisan, for example, taking out an AC/5 only takes out 25% of your primary firepower.  Taking out a single PPC, on the other hand, knocks out 50% of your firepower.  And let's not forget plain old long-range accuracy.  You can get on a string of good luck with your dice rolls, but even at short range there's always the chance that you'll miss with a shot.  Having more weapons to fire means a higher likelihood that at least 1 shot hits the target.  4 AC/5s give you twice the opportunities for hitting the target (or for a head shot) than 2 PPCs will.

That's just a specific example, though.  If you try the same thing with the 3058 variant, you find that you can approximate the max damage of the dual LB 10-X and dual AC/2s with a pair of ER PPCs & an EML...but you've now lost the benefit of being able to fire cluster rounds at the target, as well as the extra flak performance against aerial targets (which is the whole purpose behind the 3058 variant).  Not to mention that, despite again having a lighter turret, you had to allocate 25 tons for all of the extra heat sinks that didn't come with the fusion engine.

As for bracket firing & planning your heat curve so that you can fire different sets of weapons depending on the range to the target...that applies to all units, not just deep-raiding units that only have energy weapons.  And that's where autocannon & other ballistic weapons can shine.   It's a lot easier to design a unit where the majority of its heat sinks are only needed within 9 hexes, for example, than a unit that has to use most or all of its heat sinks for both the long & short range brackets...especially if you aren't using double heat sinks.  For example, I can build a 50-ton 5/8/5 'Mech with 10 tons of armor, & give it 12 heat sinks, an AC/5 with a ton of armor for long-range fire, & 3 MLs for close-range fire.  At long range, I can jump & fire until my ammo runs out, then close to ML range & fire 3/2 MLs every turn without hitting any overheat penalties (or fire all 3 MLs & not hit an overheat threshold until the 3rd consecutive turn); if I decide to close in & use all of my weapons, though, I can fire one Alpha Strike & only go up 3 on the heat scale, or fire the AC/5 & 2 MLs without overheating.  If I pull the AC/5 & put in a PPC, I still have the same range curve, but even with the 2 extra heat sinks I put in I now have to be careful firing my PPC at long range or do only limited jumping when my targets are over 9 hexes away (5 consecutive turns of jumping & firing the PPC put me at 5 heat, or I can jump/fire for 3 turns then have to limit myself to run/fire for 1 turn).  If I close within 9 hexes, I'm very limited by heat on what I can fire while jumping:  firing just the MLs is OK, but even firing 1 ML with the PPC puts me at 4 on the heat scale.  A single Alpha Strike while jumping puts me at 10 on the heat scale, not a good place to be.  Although going with the PPC version technically gives me more damage potential at range & about 13% more BV for the unit, my effective firepower at shorter ranges is actually less than the AC/5 version, because I'm limited by heat.

[Retry]

The only reason that a PPC-equipped Partisan (3025/3039 variant) "saves" on weight is because it has a 1.5 ton turret instead of the standard version's 3.5 ton turret...& because of the 2 tons of power amplifiers and 20 heat sinks it needs, the overall effect is you have an extra half-ton to play with... enough to either double your MG ammo or add 8 points of extra armor protection on.  But since you still have that half-ton of MG ammo in it, you're just as likely to become a smoking crater with an ammunition hit.  There is also the issue, however, where you are now more vulnerable to weapon critical hits.  On a standard Partisan, for example, taking out an AC/5 only takes out 25% of your primary firepower.  Taking out a single PPC, on the other hand, knocks out 50% of your firepower.  And let's not forget plain old long-range accuracy.  You can get on a string of good luck with your dice rolls, but even at short range there's always the chance that you'll miss with a shot.  Having more weapons to fire means a higher likelihood that at least 1 shot hits the target.  4 AC/5s give you twice the opportunities for hitting the target (or for a head shot) than 2 PPCs will.

"The only reason" downplays the advantage of having a lighter weapon, as the turret is an important component of the vast majority of vehicles.

The Partisan is thin-skinned and ammunition blowouts are a rather uncommon crit on vees.  You'll lose a lot more Partisans from taking normal fire than from lucky ammo crits.  But if that is really important to you, you missed a potential use of the half-ton: CASE.  That offsets the cheap cost, but an ammunition explosion no longer insta-gibs the Partisan.  Another point for the PPC Partisan.

The AC/5 array's redundancy is technically an advantage, but it's one that almost never turns up, so I don't weigh it highly.  A turret TAC is a 1-in-36 chance on the vehicle tables.  In the event of a turret crit, the probability of a weapon malfunction or weapon destruction is about 22.2%.  Net probability of 0.62% chance of happening per hit, or a MTBF of 162 hits.  When it takes only 3 PPC hits on any location to core a Partisan, there's simply not many chances for that to happen.  So it's technically an advantage, but it's not enough of a difference to make a difference, certainly not in a campaign setting.  Even in a lance-size confrontation it rarely makes a difference as the Partisan has a tendency to be dead or detracked well before that point.

Both the AC/5 and PPC have the exact same range profile.  They have the exact same accuracy.  You're referring to volume of fire, as the canon AC/5 version is more likely to hit with at least one AC/5 than the PPC version is to hit with at least one PPC.  On the flip side, the PPC version is much more likely to hit with both PPCs than the AC/5 version is to hit with all 4 AC/5s.  On the whole though, it averages out.

I have to reject the last point as misleading, and downright false in large fights.  The Partisan has 2 tons of ammo, or 10 shots of continuous fire, which is barely adequate for lance-scale 3025 engagements even considering its light armor.  It'd be a prime candidate for caseless ammunition, if it weren't for caseless's propensity to jam.

10 rounds per AC/5 is wholly inadequate for company-scale or larger engagements with larger maps in a campaign setting, in which case you'll have to with-hold firing on low-probability shots (think 10+ to-hit) to keep from running out of ammunition too early.  The PPC does not care for such trivial concerns, and can fire on 11's and 12's all day at long ranges, or even extreme and LoS ranges if Tac Ops rules are in play.  After turn 20+ (quite common in a large battle), the PPC would have likely fired more shots than the AC/5 platform, which would either have been conserving its limited ammo reserves or simply run out of ammo early on.

That's just a specific example, though.  If you try the same thing with the 3058 variant, you find that you can approximate the max damage of the dual LB 10-X and dual AC/2s with a pair of ER PPCs & an EML...but you've now lost the benefit of being able to fire cluster rounds at the target, as well as the extra flak performance against aerial targets (which is the whole purpose behind the 3058 variant).  Not to mention that, despite again having a lighter turret, you had to allocate 25 tons for all of the extra heat sinks that didn't come with the fusion engine.

Why would I want to do the same thing on the 3058 variant?  And why would I waste tonnage on an ER Medium if I was going to put 2 ER PPCs on it?  A Targeting Computer would be a better use of the spare weight.

Unlike the AC/5, the LB 10-X is actually good (if pricey in C-Bills).  Same punch as the AC/10, but with more of the good stuff (range, cluster ammo options for AA and critseeking) and less of the bad stuff (weight, heat), it's a competent and capable gun with a good grasp on its role.  The LB-X series in general are the "good" ACs, and the -10 is the poster-child.  The AC/2 isn't adding a whole lot to the Partisan 3058 though.  Ammo bins are too shallow to make good use of alternative ammo, except maybe flak, but a LB-X does that better.  Honestly, it should probably have used twin LB 2-Xs instead, but since you've mentioned it an ER PPC would have been a neat alternative to the AC/2s, if annoyingly asymmetrical.

In any case, none of that is actually relevant to the original topic, which is Conventional, vanilla Autocannons.  Not the LB-X or Ultras or the RACs or whatever.

Anyways, none of that is relevant to the topic, which is conventional Autocannons.

As for bracket firing & planning your heat curve... -snip-

I presume this is directed at Atarlost, so I'll leave that for him.

(For what it's worth, I and most of the people in my gaming group would gladly take your PPC version over the AC version 9 times out of 10.  And we'd probably swap one of the mediums for a SPL for anti-infantry, if possible.)

[kindalas]

I increased AC damage.

The AC 2 does 5 damage, the AC 5 does 7 damage, and the AC 10 does 11 damage.

The AC 20 still does 20 because it doesn't need any help.

This goes for the LBX, Rotary Ultra and Light ACs.

I still have to rejigger the BV of the ACs and then go from there.

But that's far in the future.

[RifleMech]

I keep reading that 10-12 rounds is good for most games. Now it isn't?  ???  Sure you want as much ammo as possible in a campaign but you'd also need to look a the rules of the units. A 4 AC Partisan Tank is going to serve a different role than a 2 PPC Partisan. The AC version is for Anti-Aircraft and occasional fire support. The PPC version is an support or an assault tank. It's like comparing the Sturmgeschütz IV and the Wirbelwind both use a Panzer IV chassis but have completely different roles.

The AC variant is going to be hanging back shooting at aircraft and anything that gets close to it so it's ammo supply is going to be extended. The PPC variant is going hunting and will be in the thick of things. It's not going to worry about ammo as it's got an energy weapon.

For mechs though bracket firing helps only so much. If you're still overtaxing your heat sinks bracket firing with all energy weapons doesn't help much.  Put in a ballistic weapon though you've got something to shoot while your mech cools off. Like the Marauder 3R. Fire both PPC and you're at 4 on the heat scale. Next turn fire a PPC and the AC/5 and you're back to 0 on the heat scale.

[Retry]

I keep reading that 10-12 rounds is good for most games. Now it isn't?  ??? 

For the games most people play, the Lance vs Lance matches on a 16x17, it can be enough if you're not going for special ammo but it's still shallow enough that you'll likely run dry around the final stretch.

Larger games, Company vs Company or even Battalion vs Battalion on 3x3 Mapsheets?  Especially if tac ops options like Extreme Range and LoS range are enabled?  Those matches can easily span 30+ turns.  10 rounds is not enough for a relatively long-ranged weapon like the AC/5.  20 rounds is closer to a good ammo load, and I'll still run dry quite frequently towards the end of the battle.

Granted, it's not quite as bad of a situation as a lot of those Clan battlemechs with teeny-tiny magazines (Mad Cat Prime, Vulture Prime), but in any case you really do want a more hefty magazine for bigger, longer battles.

A 4 AC Partisan Tank is going to serve a different role than a 2 PPC Partisan.

Not really.  More like Wirbelwind vs Ostwind.

In one of my succession wars campaigns a long time back, the FS player got fed up of trying and failing to find Flak ammo for the ACs and ended up just refitting the Partisans with 2 PPCs because he could get those.  He kept using it as an AA vee, and it worked out about the same.  Less overall hits because there's less guns, but on the other hand the ones that hit would core a Warrior at any non-rotor location, penetrate a Medium Strike Fighter's armor, and threshold basically any Aerospace fighter with no questions asked.  Oh, and it could fire forever on 10's, 11's and 12's in situations where the AC version would have simply run out of ammo.

The results were not disagreeable.

There were a few times they got employed as Mini-Schrecks, but that's more a convenience thanks to the PPC's ridiculous endurance, not its primary role.

Had he been able to consistently get Flak Ammo, I'm sure he would have kept the ACs and improved its effectiveness in the anti-aircraft role over the PPC variant, but in the Succession Wars you fight with the army you have, not the army you wish you had.

[Atarlost]

That depends on the unit though. There are units that can't mount DHSs.

I thought I addressed that.  Units that can't mount DHS also don't track heat from missiles.  A LRM-10 averages around 20% more damage than an AC-5 and more than half the time rolls twice on the location table.  An SRM-4 averages closer to the same damage as the AC-5, but usually rolls 2-3 locations.  Slightly more damage at all ranges and more crits at all ranges.  The AC-5's crit density advantage only applies to mechs, which can mount DHS.

Ammo explosions are always a problem but so is being shutdwn do to heat.

Being shutdown due to heat is more of a problem for autocannon platforms than energy platforms unless you have no trigger discipline.  If you do exercise proper trigger discipline overheating comes from outside sources or engine crits.  The more heat your weapons produce the more heat you can save by not firing weapons.  Compensating for an engine hit would mean holding your fire with 5 AC-5s, or holding your fire with a PPC every second turn or if you're particularly concerned about infernos even every turn.  And since, this discussion being about individual components not holistic mechs and this thread being in FD&R, we're presumably talking about customs your overheat will be the same whether you built with energy weapons or autocannons, that overheat level being whatever you as the designer and user of custom mechs think is an acceptable level of overheat. 

And ammo explosions aren't a problem if you don't have ammo.  I'd think that would be a tautology, but you seem so be arguing as if it's not. 

Ammo endurance is usually a problem however, those with few shots are usually weapons you don't want to get hit by.

This is predominantly about two AC-5s sharing 1 ton of ammo or AC-10s with 1 ton of ammo.  AC-20s are usually fielded with 3 tons of ammo on canonical units, putting them at a more acceptable 15 shots.  Ac-10s are intimidating to some targets, but these are usually targets that can generate relatively large target movement modifiers, which in turn favors weapons that can avoid running out of ammo, and that in turn loses the AC-10 its weight advantage over the PPC when mounted on mechs.  The AC-5 is never one of those weapons you particularly worry about being hit by.  Unless it's aiming at something like a dismounted mechwarrior you want to recover alive or your PC in an AToW game. 

Actually, crits are a problem for all mechs. FF takes 14 crits, HFF takes 21, ES 14 crits, XL Engine 6 crits, XXL 12 crits, XL gyro another 2,  and the smaller the engine is the fewer heat sinks it holds. And each DHS is 3 crits for IS versions.

During the Age of War crits don't matter because those techs aren't available yet.  For most of the Star League era crits don't matter to anyone but the Star League because the houses don't have those techs.  During most of the succession wars crits don't matter because those are all lostech. And during the tech renaissance DHS are the first of those techs to reappear.  And if you have DHS you have a base heat dissipation of 20 instead of 10 and get an extra 2 crit free heat dissipation for every 25 engine rating instead of only 1.  DHS tend to save crits except on lights and slow mediums.  These improve the position of energy weapons and to a lesser extent missiles relative to autocannons. When you do start to run into crits swapping energy weapons for autocannons is a last resort (except possibly to LB-10X).  First you consider if you really want the vulnerability of an XL engine.  Then you drop ferro.  I don't even bother looking at using ferro on in the first place unless I either am building very small and fast or am constrained by fluff concerns (such as being designing a depot level refit) from using endo. 

As for bracket firing & planning your heat curve so that you can fire different sets of weapons depending on the range to the target...that applies to all units, not just deep-raiding units that only have energy weapons. 

It's not just deep raiding units that use energy weapons.  And it doesn't apply usefully  to light autocannons because it takes 18 tons of AC-2s or 24 tons of AC-5s excluding ammo to properly match heat with a single medium laser.  AC-10s it's possible to couple with LRMs and AC-20s with LRMs or a PPC, but you need to add up to nontrivial heat at a sensible tonnage investment to design for bracket based heat managemtn. 

And that's where autocannon & other ballistic weapons can shine.   It's a lot easier to design a unit where the majority of its heat sinks are only needed within 9 hexes, for example, than a unit that has to use most or all of its heat sinks for both the long & short range brackets...especially if you aren't using double heat sinks. 

DHS have no impact on the ability to heat bracket other than that it becomes possible to fully cool more than a light mech on free sinks alone and you can't manage heat by brackets if you're in an icebox with no heat to manage.  If setting up brackets by heat is too hard for you perhaps you are not an expert witness.  To me it's really not that hard.  You pick your brackets and add up the heat in them in your head instead of relying on the max heat indicator in SSW or MML. 

For example, I can build a 50-ton 5/8/5 'Mech with 10 tons of armor, & give it 12 heat sinks, an AC/5 with a ton of armor for long-range fire, & 3 MLs for close-range fire.  At long range, I can jump & fire until my ammo runs out, then close to ML range & fire 3/2 MLs every turn without hitting any overheat penalties (or fire all 3 MLs & not hit an overheat threshold until the 3rd consecutive turn); if I decide to close in & use all of my weapons, though, I can fire one Alpha Strike & only go up 3 on the heat scale, or fire the AC/5 & 2 MLs without overheating.  If I pull the AC/5 & put in a PPC, I still have the same range curve, but even with the 2 extra heat sinks I put in I now have to be careful firing my PPC at long range or do only limited jumping when my targets are over 9 hexes away (5 consecutive turns of jumping & firing the PPC put me at 5 heat, or I can jump/fire for 3 turns then have to limit myself to run/fire for 1 turn).  If I close within 9 hexes, I'm very limited by heat on what I can fire while jumping:  firing just the MLs is OK, but even firing 1 ML with the PPC puts me at 4 on the heat scale.  A single Alpha Strike while jumping puts me at 10 on the heat scale, not a good place to be.  Although going with the PPC version technically gives me more damage potential at range & about 13% more BV for the unit, my effective firepower at shorter ranges is actually less than the AC/5 version, because I'm limited by heat.

You're assuming every round you're jumping 5.  Any round you run instead the PPC version will lose 2 heat.  If you are jumping every round and not facing Infernos (which at 10-18 hexes you're not) you don't care about movement penalties and can go up to +7 heat and you only build +1 per turn.  That's 8.75 damage per round compared to the AC-5's 5.  If you can't exercise that much trigger discipline perhaps the problem is not with the PPC. 

At very short range the PPC version can fire all the MLs every round.  The AC-5 can only do so if it does not jump more than 3. 

In between there's a slight advantage to firing the AC-5 and two MLs with the third fired every 3 rounds, but PPC version has 9 hexes of a substantial advantage outside ML range and 2-3 hexes of minor advantage inside AC-5/PPC minimum range compared to the AC-5 version's minor advantage over 6-7 hexes in between.  And that advantage erodes further if it is reasonable to fire the PPC instead of the MLs in their long or with a poor gunner or fast opponent even medium bracket. 

You're also assuming that only the AC-5 and PPC are the only weapons in competition.  There's also the LRM-10, which does slightly more damage than the AC-5 with significantly more hit locations and thus crit chances.  It has to stop firing sooner as you close with your opponent, but it also starts firing earlier and has the unique among basic weapons ability to fire over obstacles if a spotter is available. 

[RifleMech]

Granted, it's not quite as bad of a situation as a lot of those Clan battlemechs with teeny-tiny magazines (Mad Cat Prime, Vulture Prime), but in any case you really do want a more hefty magazine for bigger, longer battles.

Exactly. So 20 rounds is okay for most games, and more is better for longer games and campaigns. Running out of ammo happens though. Which is why there's ammo carriers and reloading rules.

Many OMNI configurations are for short heavy combat not so much longer campaigns.

Not really.  More like Wirbelwind vs Ostwind.

Not really as its like replacing four HMGs with one LAC/2. The big punch of the PPC is more like that of a MBT than an AAT.

In one of my succession wars campaigns a long time back, the FS player got fed up of trying and failing to find Flak ammo for the ACs and ended up just refitting the Partisans with 2 PPCs because he could get those.  He kept using it as an AA vee, and it worked out about the same.  Less overall hits because there's less guns, but on the other hand the ones that hit would core a Warrior at any non-rotor location, penetrate a Medium Strike Fighter's armor, and threshold basically any Aerospace fighter with no questions asked.  Oh, and it could fire forever on 10's, 11's and 12's in situations where the AC version would have simply run out of ammo.

The results were not disagreeable.

There were a few times they got employed as Mini-Schrecks, but that's more a convenience thanks to the PPC's ridiculous endurance, not its primary role.

Now that's more like replacing the 20mms with 8.8cms. It certainly works. Your AA Tank still shouldn't be right on the front line though.

Had he been able to consistently get Flak Ammo, I'm sure he would have kept the ACs and improved its effectiveness in the anti-aircraft role over the PPC variant, but in the Succession Wars you fight with the army you have, not the army you wish you had.

That's true. It's also a problem with the availability ratings. Flak has a Tech Rating of B and pretty much every planet could use Flak Ammo. The availability should be better than E-E-F.

[RifleMech]

I thought I addressed that.  Units that can't mount DHS also don't track heat from missiles.  A LRM-10 averages around 20% more damage than an AC-5 and more than half the time rolls twice on the location table.  An SRM-4 averages closer to the same damage as the AC-5, but usually rolls 2-3 locations.  Slightly more damage at all ranges and more crits at all ranges.  The AC-5's crit density advantage only applies to mechs, which can mount DHS.

Not really. Low Tech BattleMechs and IndustrialMechs still track heat and can't mount DHS. Also Engine Type can change if DHS are used or how they're used. An XXL Engine generates 6 heat when running. With 10 DHS included leaves 7 DHS that can be used for weapons. That changes how you'd do things.

Being shutdown due to heat is more of a problem for autocannon platforms than energy platforms unless you have no trigger discipline.  If you do exercise proper trigger discipline overheating comes from outside sources or engine crits.  The more heat your weapons produce the more heat you can save by not firing weapons.  Compensating for an engine hit would mean holding your fire with 5 AC-5s, or holding your fire with a PPC every second turn or if you're particularly concerned about infernos even every turn.  And since, this discussion being about individual components not holistic mechs and this thread being in FD&R, we're presumably talking about customs your overheat will be the same whether you built with energy weapons or autocannons, that overheat level being whatever you as the designer and user of custom mechs think is an acceptable level of overheat. 

Not really. 5 AC/5s only generate 5 heat. A single PPC generates 10 heat. A mech with a damaged SFE can fire all 5 AC/5s and still be heat neutral. Or it could run and fire 3 AC/5s. The PPC though will generate an extra 5 heat on the first shot and it'll be climbing from there unless you don't fire.

And ammo explosions aren't a problem if you don't have ammo.  I'd think that would be a tautology, but you seem so be arguing as if it's not. 

True but energy weapons also generate more heat than autocannons. Unless you've got a low tech Mech you're more likely to overheat with energy weapons than you will with Autocannons.

This is predominantly about two AC-5s sharing 1 ton of ammo or AC-10s with 1 ton of ammo.  AC-20s are usually fielded with 3 tons of ammo on canonical units, putting them at a more acceptable 15 shots.  Ac-10s are intimidating to some targets, but these are usually targets that can generate relatively large target movement modifiers, which in turn favors weapons that can avoid running out of ammo, and that in turn loses the AC-10 its weight advantage over the PPC when mounted on mechs.  The AC-5 is never one of those weapons you particularly worry about being hit by.  Unless it's aiming at something like a dismounted mechwarrior you want to recover alive or your PC in an AToW game. 

Light units worry about being hit by everything. Obviously being hit by an AC/5 is better than being hit by an AC/10 but it still takes a big chunk of a light mech's armor.

During the Age of War crits don't matter because those techs aren't available yet.  For most of the Star League era crits don't matter to anyone but the Star League because the houses don't have those techs.  During most of the succession wars crits don't matter because those are all lostech. And during the tech renaissance DHS are the first of those techs to reappear.  And if you have DHS you have a base heat dissipation of 20 instead of 10 and get an extra 2 crit free heat dissipation for every 25 engine rating instead of only 1.  DHS tend to save crits except on lights and slow mediums.  These improve the position of energy weapons and to a lesser extent missiles relative to autocannons. When you do start to run into crits swapping energy weapons for autocannons is a last resort (except possibly to LB-10X).  First you consider if you really want the vulnerability of an XL engine.  Then you drop ferro.  I don't even bother looking at using ferro on in the first place unless I either am building very small and fast or am constrained by fluff concerns (such as being designing a depot level refit) from using endo. 

Actually, Advanced Tech began being introduced during the Reunification War. By the time the Star League fell, all these technologies were commonly available. The Terran Hegemony just used them more often as they had more funds. And while DHS were the first to be reintroduced. True DHS weren't commonly available outside the FS until 3045. Before then there's DHS-P. They don't fit in the engine. That changes how much heat reduction you have.

It's not just deep raiding units that use energy weapons.  And it doesn't apply usefully  to light autocannons because it takes 18 tons of AC-2s or 24 tons of AC-5s excluding ammo to properly match heat with a single medium laser.  AC-10s it's possible to couple with LRMs and AC-20s with LRMs or a PPC, but you need to add up to nontrivial heat at a sensible tonnage investment to design for bracket based heat managemtn. 

True but if you're trying to match heat with autocannons to energy weapons you're doing it wrong. Lighter units are also less likely to mount heavier weapons. You're looking more at MLasers, SRMs, and LRM-5s. Occasionally you see AC/2s but they're not common. Their low heat also means they can fire all the time.

DHS have no impact on the ability to heat bracket other than that it becomes possible to fully cool more than a light mech on free sinks alone and you can't manage heat by brackets if you're in an icebox with no heat to manage.  If setting up brackets by heat is too hard for you perhaps you are not an expert witness.  To me it's really not that hard.  You pick your brackets and add up the heat in them in your head instead of relying on the max heat indicator in SSW or MML. 

Being able to fire your weapons all the time is better than just firing them in a bracket. DHS also means you can use more powerful energy weapons without overheating. You can easily go from 2 PPCs to 4 ER MLasers using Bracket Fire and DHS.

You're assuming every round you're jumping 5.  Any round you run instead the PPC version will lose 2 heat.  If you are jumping every round and not facing Infernos (which at 10-18 hexes you're not) you don't care about movement penalties and can go up to +7 heat and you only build +1 per turn.  That's 8.75 damage per round compared to the AC-5's 5.  If you can't exercise that much trigger discipline perhaps the problem is not with the PPC. 

At very short range the PPC version can fire all the MLs every round.  The AC-5 can only do so if it does not jump more than 3. 

 :o

3 Medium Lasers generate 9 heat. An AC/5 generates 1 heat. A PPC generates 10 heat. A Mech can jump 5 hexes and fire the AC/5 and not generate the heat just firing 3 MLasers or 1 PPC will generate.

In between there's a slight advantage to firing the AC-5 and two MLs with the third fired every 3 rounds, but PPC version has 9 hexes of a substantial advantage outside ML range and 2-3 hexes of minor advantage inside AC-5/PPC minimum range compared to the AC-5 version's minor advantage over 6-7 hexes in between.  And that advantage erodes further if it is reasonable to fire the PPC instead of the MLs in their long or with a poor gunner or fast opponent even medium bracket. 

 :-\

A PPC and AC/5 have the exact same ranges. There is no range advantage unless you want to disengage the PPC's inhibitors and risk damage.

You're also assuming that only the AC-5 and PPC are the only weapons in competition.  There's also the LRM-10, which does slightly more damage than the AC-5 with significantly more hit locations and thus crit chances.  It has to stop firing sooner as you close with your opponent, but it also starts firing earlier and has the unique among basic weapons ability to fire over obstacles if a spotter is available.

You're assuming an average number of missiles will hit, or you're firing from an Aerospace Unit. And 1 point isn't much. Being able to fire indirectly is an advantage however, you also have less ammo than the AC/5 while generating 4 times the heat.

And how does any of this make for a better Autocannon?

[Retry]

Exactly. So 20 rounds is okay for most games, and more is better for longer games and campaigns. Running out of ammo happens though. Which is why there's ammo carriers and reloading rules.

Many OMNI configurations are for short heavy combat not so much longer campaigns.

20 turns of continuous fire is, if you don't want to make heavy use of alternative ammunition.

The Partisan has 10.

(The Partisan also needs a good 40 minutes for a regular tech team to fully reload the machine's AC/5s in the field.  Not having to worry about that is a nice advantage for the PPC version.)

Not really as its like replacing four HMGs with one LAC/2. The big punch of the PPC is more like that of a MBT than an AAT.


Now that's more like replacing the 20mms with 8.8cms. It certainly works. Your AA Tank still shouldn't be right on the front line though.

8.8cm would be more like one of the lighter artillery guns used in a flak attack, like a Thumper.  Autocannons "technically" fire a burst of shells, but on the board that's abstracted into a single 5-point hit.  I could fluff an "AA PPC" variant as firing a small shot every half second instead of a big blob every 10, it'd perform the same under the rules.

It's not a perfect comparison as the Ostwind has 1 gun vs the PPC Partisan's 2, but it's a lot closer than saying a PPC Partisan is like a StuG.

(The AA tank wasn't on the front lines.  It was used the same way as the original Partisan.)

That's true. It's also a problem with the availability ratings. Flak has a Tech Rating of B and pretty much every planet could use Flak Ammo. The availability should be better than E-E-F.

We've house-ruled it to be better since then.  That helps its AA role, but we had to make other tweaks to make it more effective and fun to use as a general-purpose gun.

[RifleMech]

I could swear I replied to this.

20 turns of continuous fire is, if you don't want to make heavy use of alternative ammunition.

The Partisan has 10.

To be accurate that's 10 per AC. Less depending on the alternate ammo.

(The Partisan also needs a good 40 minutes for a regular tech team to fully reload the machine's AC/5s in the field.  Not having to worry about that is a nice advantage for the PPC version.)8.8cm would be more like one of the lighter artillery guns used in a flak attack, like a Thumper.  Autocannons "technically" fire a burst of shells, but on the board that's abstracted into a single 5-point hit.  I could fluff an "AA PPC" variant as firing a small shot every half second instead of a big blob every 10, it'd perform the same under the rules.

True not worrying about ammo is a plus and if it takes 40 minutes to reload the Partisan, what about the Fighters?  There's travel times and then reloading and refueling.

It's not a perfect comparison as the Ostwind has 1 gun vs the PPC Partisan's 2, but it's a lot closer than saying a PPC Partisan is like a StuG.

Maybe the ZSU-57-2?  I know a 10 point hit will ruin anyone's day but so will a 2 point hit against Fighters. That's why AC/2s are used in AA roles. The AC/2 isn't so good against heavy armor units though. Its annoying but doesn't do much damage. The PPC though can take big chunks out of the armor if it doesn't blow it all off. That what I'm thinking the PPC Partisan is more a StuG than an AA Tank. Its wanting to take big chunks out of ground units.

(The AA tank wasn't on the front lines.  It was used the same way as the original Partisan.)We've house-ruled it to be better since then.  That helps its AA role, but we had to make other tweaks to make it more effective and fun to use as a general-purpose gun.

Cool. It would be nice if there were ammo as described in the Partisan's fluff.

[Fear Factory]

Abou and I use this in games... haven't looked back.

- Autocannons cause standard damage if you roll the TN on the to-hit roll. If you roll above the TN, apply a +2 damage bonus. For Ultra Autocannons split the bonus between both shots. For LB-X, put the bonus on the cluster roll.

So if you have an AC/5, need a 7 to hit, and you roll an 8, you cause 7 damage (5, +2 damage bonus for rolling above TN). If you rolled a 7 you would cause 5 damage.

Haven't thought much about rotary... but splitting the bonus across the first two shots would be enough.

This gives them some extra umph and makes them operate differently when compared to energy and missile weapons.

[Daryk]

I like that idea, but a flat +2 seems odd.  I'd think scaling it with the MOS would make more sense.  Maybe +1 damage per 2 points of MOS rounded up (so +1 at 1 or 2, +2 at 3 or 4, etc.).  Ultras and Rotaries could just get +1 damage per MOS, split as evenly as possible among the shots.  A bonus to the Cluster Roll for LB-Xs makes perfect sense!  :thumbsup:

[Retry]

Either method basically sounds like a modified version of the Tac Ops direct hit rule, and probably doesn't play nicely with it.

I had good results in my group simply making rapid-fire the default of ACs, and giving Ultras a greatly improved rapid-fire mode.  That, and a few Quality-of-life improvements to ACs, got Autocannons as a whole feeling very respectable.  Should've been pretty easy to calculate the new BV too, had I cared enough to do so.

[Fear Factory]

I like that idea, but a flat +2 seems odd.  I'd think scaling it with the MOS would make more sense.  Maybe +1 damage per 2 points of MOS rounded up (so +1 at 1 or 2, +2 at 3 or 4, etc.).  Ultras and Rotaries could just get +1 damage per MOS, split as evenly as possible among the shots.  A bonus to the Cluster Roll for LB-Xs makes perfect sense!  :thumbsup:

Nah, it's easier to remember when all you have to worry about is the TN or above. BattleTech is 'complicated' enough.

Either method basically sounds like a modified version of the Tac Ops direct hit rule, and probably doesn't play nicely with it.

I had good results in my group simply making rapid-fire the default of ACs, and giving Ultras a greatly improved rapid-fire mode.  That, and a few Quality-of-life improvements to ACs, got Autocannons as a whole feeling very respectable.  Should've been pretty easy to calculate the new BV too, had I cared enough to do so.

TacOps... not worried about it.

[Retry]

TacOps... not worried about it.

Well, I and my group do use Tac Ops, so I'd prefer the solution fits snugly in it.

[Fear Factory]

Well, I and my group do use Tac Ops, so I'd prefer the solution fits snugly in it.

It's all optional anyway. Use as you see fit.

[Atarlost]

Not really. Low Tech BattleMechs and IndustrialMechs still track heat and can't mount DHS.

Tracing the quote chain this is about LAC-2s.  There's damning with faint praise, and then there's invoking industrialmechs too small to mount an AC-5 as a military platform important enough to design and put into production a weapon that is bad everywhere else. 

Also Engine Type can change if DHS are used or how they're used. An XXL Engine generates 6 heat when running. With 10 DHS included leaves 7 DHS that can be used for weapons. That changes how you'd do things.

Again, this quote chain is about the LAC-2, which is 5 tons if you want ammo for it.  So, what energy weapon is 5 tons and has range brackets equal to or better than the LAC-2?  The ERLL.  So 6 movement heat plus 12 weapon heat?  Yeah, still under the 20 free freezers. 

Not really. 5 AC/5s only generate 5 heat. A single PPC generates 10 heat. A mech with a damaged SFE can fire all 5 AC/5s and still be heat neutral. Or it could run and fire 3 AC/5s. The PPC though will generate an extra 5 heat on the first shot and it'll be climbing from there unless you don't fire.

You're taking ratios as concrete mech designs.  If you're heat balanced and you lose an engine crit not firing a PPC half the time or a LL 62.5% of the time or dropping 1.67 MLs rebalances your heat.  It takes not firing 5 AC-5s or AC-2s or 1.67 AC-10s or 0.71 AC-20s to cover the same heat.  If you take 2 engine crits on a base heatsink only energy mech you'll cook off your ammo from movement heat.  If you take 2 engine crits on an energy boat you're down one PPC or 1.25 LLs or 3.33 MLs. 

An autocannon boat that isn't wasting heatsinks is always going to have some AC-10s or AC-20s so the real ratio of damage lost to heat lost is not as bad as the pure AC-5 ratio, but it's always going to be worse than the LL/PPC ratio. 

True but energy weapons also generate more heat than autocannons. Unless you've got a low tech Mech you're more likely to overheat with energy weapons than you will with Autocannons.

If you're overheating to a degree that negatively impacts your performance you're either firing when you shouldn't, being hit by heat generating weapons, passing through +5 and +8 heat on your way to +9 to activate your TSM, you have a particularly stupid heat cycle that puts you to +5 (the Marauder or a mech that's taken an engine hit), or you already know your next turn will be spent jetting behind an obstruction to cool off.  There's no reason to ever go over +9 heat other than if you know you will not be in the fight next turn or if you have been hit unexpectedly by inferno or plasma weapons and the only other reason to go to over +7 is to activate TSM.  If you're having trouble with energy boats overheating the fault lies not in your mech but in yourself. 

Light units worry about being hit by everything. Obviously being hit by an AC/5 is better than being hit by an AC/10 but it still takes a big chunk of a light mech's armor.

A hit that doesn't penetrate doesn't much matter when you get hit on an 10+.  Getting hit twice in the same location when the enemy needs high rolls to hit is a lot less likely than getting hit once with a 10 point gun that will crit or will crit anywhere but the center torso. 

Actually, Advanced Tech began being introduced during the Reunification War. By the time the Star League fell, all these technologies were commonly available. The Terran Hegemony just used them more often as they had more funds. And while DHS were the first to be reintroduced. True DHS weren't commonly available outside the FS until 3045. Before then there's DHS-P. They don't fit in the engine. That changes how much heat reduction you have.

If you are designing a Terran Hegemony mech between 2487 and 2567 it might be possible for crit concerns to push the AC-10 over the PPC.  The InterOps common dates for all advanced tech are after the recovery.  I'll admit I have misread the date for Endo-steel by a decade, but it's a very unusual design that can run out of crits with just endosteel, but you might be able to contrive one that makes sense. 

Being able to fire your weapons all the time is better than just firing them in a bracket. DHS also means you can use more powerful energy weapons without overheating. You can easily go from 2 PPCs to 4 ER MLasers using Bracket Fire and DHS.

Bracket firing means using the same heatsink twice (or in extreme cases thrice).  You need 12 heatsinks to fire two LRM-20s.  You need 12 heastinks to fire four MLs.  You don't need 24 heatsinks on a mech with two LRM-20s and four MLs.  You only need 12 plus any you want for movement.  With DHS the weapons may change, but between two ERPPCs and 10 MLs with 15 freezers or two ERPPCs and 4 MLs with 20 freezers the former the former does 50 damage at short range while the latter does 40 just by assuming the ERPPCs won't be fired at short range and putting on MLs at 1 ton each instead of 2.5 tons each by double counting the heatsinks. 

True but if you're trying to match heat with autocannons to energy weapons you're doing it wrong. Lighter units are also less likely to mount heavier weapons. You're looking more at MLasers, SRMs, and LRM-5s. Occasionally you see AC/2s but they're not common. Their low heat also means they can fire all the time.

If your heat doesn't match you aren't using your heatsinks twice.  Autocannons thus can't benefit from bracket firing as a practical matter except with AC-10s and AC-20s.  This is a response to theagent, who was not talking about lighter units.  His example was a 50 tonner.  He was claiming that one AC-5 and three ML constituted a bracket fire setup.   

Whether you can fire a weapon every turn depends on whether you have the heatsinks for it and how much ammo you have.  It also doesn't mean you should have the weapon at all.  The ur-example of a weapon you fire every round but would be better off without is the AC-5 on the Marauder.  If you had 4 heatsinks instead you could fire your PPCs more and do as much damage while having 5 tons for whatever you want. 

3 Medium Lasers generate 9 heat. An AC/5 generates 1 heat. A PPC generates 10 heat. A Mech can jump 5 hexes and fire the AC/5 and not generate the heat just firing 3 MLasers or 1 PPC will generate.

Heat generated doesn't matter.  Damage output over time without suffering heat penalties matters.  They're related, but not identical. 

A PPC and AC/5 have the exact same ranges. There is no range advantage unless you want to disengage the PPC's inhibitors and risk damage.

Not a range advantage, an advantage at range, ie. 10-18 hexes where the shorter ranged MLs aren't applicable.  The advantage being that a PPC puts out 10 damage every round it fires and fires 7 rounds in 8 for an average potential damage per round of 8.75 while an AC-5 only does 5 potential damage per round.  Multiply both by your odds of hitting, but since the range brackets are identical they cancel out in the comparison. 

You're assuming an average number of missiles will hit, or you're firing from an Aerospace Unit. And 1 point isn't much. Being able to fire indirectly is an advantage however, you also have less ammo than the AC/5 while generating 4 times the heat.

I'm assuming that over many rounds on an average round an average number of missiles will hit.  That's how statistics and probability work. 

And how does any of this make for a better Autocannon?

Defending the validity of the exercise against people who don't want there to be a better Autocannon because they refuse to do the math.  Identifying when the autocannons fall short: people who mistakenly believe the problem starts with DHS may suggest solutions that only apply to the Star League and Foundtech eras instead of solutions that apply to all problem eras.  Identifying the magnitude of the problem.  AC-10s are close on mechs and are The tank gun so they need little if any buffing.  AC-5s need serious help, but many of the boosts would make them overpowered in the lostech era.  I'm of the opinion that AC-2 damage doesn't matter because they're primarily for lawndart and crit fishing, but they're also not in danger of becoming overpowered.  I'm also of the opinion that AC-20 damage is chunky enough to give value apart from their unimpressive damage per ton, though in the advanced ammo era their small ammo bins that lose 20% to roundoff prevent them from making the comeback relative to LBX that the other standard autocannons do. 

To avoid overtuning the AC-10, especially on tanks, I would avoid a damage increase.  For the sake of the AC-10 and in the advanced ammo era the AC-20 I'd like to see an ammo bin size increase to at least 120 damage and possibly 160.  And I'd like to see an ammo explosion fix.  Something fairly extreme like rolling on the number of crits table again (probably penalized by CASE) to determine how many individual rounds explode.  I'm somewhat resigned to there not being a good fix for the AC-5 that isn't individual to it. 

[RifleMech]

Tracing the quote chain this is about LAC-2s.  There's damning with faint praise, and then there's invoking industrialmechs too small to mount an AC-5 as a military platform important enough to design and put into production a weapon that is bad everywhere else.

Again, this quote chain is about the LAC-2, which is 5 tons if you want ammo for it.  So, what energy weapon is 5 tons and has range brackets equal to or better than the LAC-2?  The ERLL.  So 6 movement heat plus 12 weapon heat?  Yeah, still under the 20 free freezers.   

Nope it was about units that don't mount DHS. Industrials and LowTech Mechs don't mount DHS. A Mech with a FCE or ICE is going to have to mount enough single heat sinks to deal with the heat. So that 5 ton ERLL is going to weigh 17.5 tons vs the LAC/2 at 7 tons.

Also while the XXL with 10 DHS and ERLL will generate a total of 18 heat there's not much else it can do without overheating. It's also more vulnerable to Flame Weapons and an XL or SFE.

You're taking ratios as concrete mech designs.  If you're heat balanced and you lose an engine crit not firing a PPC half the time or a LL 62.5% of the time or dropping 1.67 MLs rebalances your heat.  It takes not firing 5 AC-5s or AC-2s or 1.67 AC-10s or 0.71 AC-20s to cover the same heat.  If you take 2 engine crits on a base heatsink only energy mech you'll cook off your ammo from movement heat.  If you take 2 engine crits on an energy boat you're down one PPC or 1.25 LLs or 3.33 MLs. 

An autocannon boat that isn't wasting heatsinks is always going to have some AC-10s or AC-20s so the real ratio of damage lost to heat lost is not as bad as the pure AC-5 ratio, but it's always going to be worse than the LL/PPC ratio. 

How are the heat sinks wasted when they allow you to keep operating even under full heat? That's like saying a Mech with just a PPC and DHS would be wasting heat sinks. When really those extra heat sinks allow the PPC to continue firing long after heat would have shut the mech down.

If you're overheating to a degree that negatively impacts your performance you're either firing when you shouldn't, being hit by heat generating weapons, passing through +5 and +8 heat on your way to +9 to activate your TSM, you have a particularly stupid heat cycle that puts you to +5 (the Marauder or a mech that's taken an engine hit), or you already know your next turn will be spent jetting behind an obstruction to cool off.  There's no reason to ever go over +9 heat other than if you know you will not be in the fight next turn or if you have been hit unexpectedly by inferno or plasma weapons and the only other reason to go to over +7 is to activate TSM.  If you're having trouble with energy boats overheating the fault lies not in your mech but in yourself. 

Some mechs have more heat sinks than other though. It's a lot easier to remain under 9 heat with a Fussion engine and DHS than it is with a ICE and singles.

A hit that doesn't penetrate doesn't much matter when you get hit on an 10+.  Getting hit twice in the same location when the enemy needs high rolls to hit is a lot less likely than getting hit once with a 10 point gun that will crit or will crit anywhere but the center torso. 

Every hit matters. Some just matter more.

If you are designing a Terran Hegemony mech between 2487 and 2567 it might be possible for crit concerns to push the AC-10 over the PPC.  The InterOps common dates for all advanced tech are after the recovery.  I'll admit I have misread the date for Endo-steel by a decade, but it's a very unusual design that can run out of crits with just endosteel, but you might be able to contrive one that makes sense. 

Prototype Endo takes more crits. Depending on the year DHS aren't available so that could mean more singles being installed.

Bracket firing means using the same heatsink twice (or in extreme cases thrice).  You need 12 heatsinks to fire two LRM-20s.  You need 12 heastinks to fire four MLs.  You don't need 24 heatsinks on a mech with two LRM-20s and four MLs.  You only need 12 plus any you want for movement.  With DHS the weapons may change, but between two ERPPCs and 10 MLs with 15 freezers or two ERPPCs and 4 MLs with 20 freezers the former the former does 50 damage at short range while the latter does 40 just by assuming the ERPPCs won't be fired at short range and putting on MLs at 1 ton each instead of 2.5 tons each by double counting the heatsinks. 

That's true but your're also not using all of your weapons a neutral unit can.

If your heat doesn't match you aren't using your heatsinks twice.  Autocannons thus can't benefit from bracket firing as a practical matter except with AC-10s and AC-20s.  This is a response to theagent, who was not talking about lighter units.  His example was a 50 tonner.  He was claiming that one AC-5 and three ML constituted a bracket fire setup. 

Again using heat sinks like that means you're not using your mech's full weaponry.
 

Whether you can fire a weapon every turn depends on whether you have the heatsinks for it and how much ammo you have.  It also doesn't mean you should have the weapon at all.  The ur-example of a weapon you fire every round but would be better off without is the AC-5 on the Marauder.  If you had 4 heatsinks instead you could fire your PPCs more and do as much damage while having 5 tons for whatever you want. 

True you can replace the AC/5 with heat sinks and other stuff.

Heat generated doesn't matter.  Damage output over time without suffering heat penalties matters.  They're related, but not identical. 

And yet overheating makes delivering damage more difficult.

Not a range advantage, an advantage at range, ie. 10-18 hexes where the shorter ranged MLs aren't applicable.  The advantage being that a PPC puts out 10 damage every round it fires and fires 7 rounds in 8 for an average potential damage per round of 8.75 while an AC-5 only does 5 potential damage per round.  Multiply both by your odds of hitting, but since the range brackets are identical they cancel out in the comparison. 

  And the point would be?

Defending the validity of the exercise against people who don't want there to be a better Autocannon because they refuse to do the math.  Identifying when the autocannons fall short: people who mistakenly believe the problem starts with DHS may suggest solutions that only apply to the Star League and Foundtech eras instead of solutions that apply to all problem eras.  Identifying the magnitude of the problem.  AC-10s are close on mechs and are The tank gun so they need little if any buffing.  AC-5s need serious help, but many of the boosts would make them overpowered in the lostech era.  I'm of the opinion that AC-2 damage doesn't matter because they're primarily for lawndart and crit fishing, but they're also not in danger of becoming overpowered.  I'm also of the opinion that AC-20 damage is chunky enough to give value apart from their unimpressive damage per ton, though in the advanced ammo era their small ammo bins that lose 20% to roundoff prevent them from making the comeback relative to LBX that the other standard autocannons do. 

To avoid overtuning the AC-10, especially on tanks, I would avoid a damage increase.  For the sake of the AC-10 and in the advanced ammo era the AC-20 I'd like to see an ammo bin size increase to at least 120 damage and possibly 160.  And I'd like to see an ammo explosion fix.  Something fairly extreme like rolling on the number of crits table again (probably penalized by CASE) to determine how many individual rounds explode.  I'm somewhat resigned to there not being a good fix for the AC-5 that isn't individual to it.

I have done math and DHS do have an effect. A Mech with 11 DHS and 2 PPCs can run and fire and not worry about overheating and take only 15 tons. The same Mech though  may not be able to mount 2 AC/5s with 2 tons of ammo would as it'd weigh 18 tons. If the Heat Sinks were singles though the 2 PPCs and 22 heat sinks would weigh 26 tons. The 2 AC/5s still weigh 18 tons. So yes, DHS do give a big advantage to Energy Weapons.

The issue goes back even further though. It used to be all heat sinks required critical slots. So even if a mech had the tonnage for energy weapons and heat sinks it may not have the critical space to mount all of them. That gave the lower heat Autocannons an advantage over Energy Weapons. Placing HS in the engine gave the advantage to Energy Weapons. Essentially they got free crits.

Personally, I'd love for their to be Improved Autocannons. In fact we do have Improved Autocannons. What would be nice is if they were more available and a more improved MK II model was available.

[Atarlost]

Nope it was about units that don't mount DHS. Industrials and LowTech Mechs don't mount DHS. A Mech with a FCE or ICE is going to have to mount enough single heat sinks to deal with the heat. So that 5 ton ERLL is going to weigh 17.5 tons vs the LAC/2 at 7 tons.

Trace the quote chain again.  You'll find you said:

The LAC-2 is good for units that can't mount a larger AC and still want to reach out to 18 hexes.

You're just meandering into crazy places where industrialmechs are important enough combat units to design weapons that are garbage on everything else including ICE powered vehicles. 

Also while the XXL with 10 DHS and ERLL will generate a total of 18 heat there's not much else it can do without overheating. It's also more vulnerable to Flame Weapons and an XL or SFE.

Again, this is your response to my response to your response to my claim that LAC-2s stand out as bad among other autocannons.  The only justification you or anyone else provided for LAC-2s was that something doesn't have the tonnage for an AC-5 but wants to fire out to 18 hexes.  This thus assumes a mech that can't do *anything* other than run and fire its ERLL because the 5 tons for the ERLL or the LAC-2 and ammo are all it has to spare.  You're trying to move the goalposts without providing any reason why anyone should ever mount the gun in question if there's enough tonnage to mount anything else. 

How are the heat sinks wasted when they allow you to keep operating even under full heat? That's like saying a Mech with just a PPC and DHS would be wasting heat sinks. When really those extra heat sinks allow the PPC to continue firing long after heat would have shut the mech down.

Yes.  If a mech has DHS and only mounts a PPC as its sole weapon it is wasting heatsinks.  Unless it's also mounting a PPC capacitor and 5 or more jumpjets or the PPC is a heavy or ER model or it's mounting stealth armor or otherwise making use of all of its heatsinks.  If it doesn't jump it's leaving heat dissipation worth 4 tons on the table.  I don't see how this is even under contention.  If you buy a year subscription to a streaming service and only use it for one week of binge watching that is also waste. 
 

Some mechs have more heat sinks than other though. It's a lot easier to remain under 9 heat with a Fussion engine and DHS than it is with a ICE and singles.

You keep coming back to ICE.  The only real combat units that use ICE are vehicles that can never overheat at all by definition.  It is not hard to remain under 9 heat with single heatsinks.  You just have to do some simple arithmetic instead of blindly smashing the big red Alpha Strike button. 

Every hit matters. Some just matter more.

Hardly.  Impaired functionality matters.  A hit that doesn't contribute to impairing functionality because the target is too evasive for you to hit again may as well not have happened.  If you're tracking C-bills repairing armor has some cost, but because of the weight multiplier 5 points of armor cost less on a 20 ton mech than on an 80 ton mech. 

Prototype Endo takes more crits. Depending on the year DHS aren't available so that could mean more singles being installed.

No one uses prototype endo.  Theoretically the Hegemony must have built a prototype, but it was never a deployed unit, doesn't have stats, and likely wasn't armed with anything but load simulating weights because its job was to test a skeleton not to fight.  And it's rare to run out of crits on just endo without either ferro or the really hot running ER energy weapons, which are not required to make medium autocannons look bad. 

That's true but your're also not using all of your weapons a neutral unit can.


 

Again using heat sinks like that means you're not using your mech's full weaponry.

Because you spend less on heatsinks you can only use where the ranges intersect you have more weaponry.  For every 1 ton of ML you aren't firing with your LRMs at 7-9 hexes with your LRMs you're saving 1.5 tons of DHS that you weren't going to use either past 9 hexes or within LRM minimum range.  That's not waste.  That's trading at an advantage.  Because of those savings you wind up with more guns.  The heatsinks you don't need if you stop firing your low efficiency long range weapons like ERPPCs or ERLLs leave the mass to mount far more higher efficiency short range weapons like MLs or, if working with clantech, cERMLs.  Such designs do the same long range damage and more short range damage than designs that attempt to sink the alpha strike. 
 

And yet overheating makes delivering damage more difficult.

That's why you exercise some expletive trigger discipline. 

And the point would be?

That a gun that does 10 damage is better than a gun that does 5 damage.  If you don't like the example blame theagent.  He's the one that proposed example mechs with a PPC and a single AC-5.  While trying to defend the AC-5 no less. 

I have done math and DHS do have an effect. A Mech with 11 DHS and 2 PPCs can run and fire and not worry about overheating and take only 15 tons. The same Mech though  may not be able to mount 2 AC/5s with 2 tons of ammo would as it'd weigh 18 tons. If the Heat Sinks were singles though the 2 PPCs and 22 heat sinks would weigh 26 tons. The 2 AC/5s still weigh 18 tons. So yes, DHS do give a big advantage to Energy Weapons.

This is irrelevant to heat bracketing weapons.  For weapon bracket heat management what matters is that heatsinks have some mass (and when relevant crits) which can be used for other things if you contrive to need fewer of them.  Yes, DHS make high heat weapons better, but that was a response to you disputing the existence of bracket heat management in the DHS era. 

The issue goes back even further though. It used to be all heat sinks required critical slots. So even if a mech had the tonnage for energy weapons and heat sinks it may not have the critical space to mount all of them. That gave the lower heat Autocannons an advantage over Energy Weapons. Placing HS in the engine gave the advantage to Energy Weapons. Essentially they got free crits.

The stated premises are true.  The unstated premise that this made a difference is not.  The conclusion is thus false. 

If a Shadow Hawk trades its AC-5 and ammo for a PPC and two heatsinks it winds up with 33 open crits.  11 heatsinks are hidden in the engine.  That's 22 crits open even under Battledroids. 

If a Rifleman trades its two AC-5s and ammo for a PPC and 10 heatsinks it winds up with 31 open crits.  Only 9 heatsinks are hiding in the engine.  Again, 22 crits open under Battledroids. 

If a Wolverine trades its AC-5 and ammo for a PPC and two heatsinks it winds up with 32 open crits.  11 heatsinks are hidden in the engine so it "only" has 21 crits upen under Battledroids.

If a Marauder has its AC-5 and ammo removed for the 4 desperately needed heatsinks to fire both of the PPCs it already has and say a gratuitous large laser (ie. the MAD-3D) it has 31 open crits. A whopping 12 heatsinks are hidden in the engine which under battledroids leaves it with *drumroll* 29 open crits. 

That's it.  Those are the mechs from Battledroids that have the only autocannon in the Battledroids rules.  None of them are constrained to use it by a lack of critical slots for heatsinks.  The change makes ammo bin crits more likely, but ammo bin crits are the tiebreaker that makes the PPC better than the AC-10 on mechs.  The AC-5 is worse without needing to go to a tiebreaker. 

Personally, I'd love for their to be Improved Autocannons. In fact we do have Improved Autocannons. What would be nice is if they were more available and a more improved MK II model was available.

Improved autocannons, unless introduced in 2370 and retconned to replace the autocannons we have, don't fix the problem because the problem for the AC-5 starts once both LRMs and SRMs exist.  The problem is worst in the SHS era because for most of the DHS era the AC-5 and AC-10 are supposed to be eclipsed by the LB-10X so it doesn't much matter if they're also eclipsed by other weapons or weapon combinations.  If you see anything with a standard autocannon (other than class 20s on aerospace units purely because they're disallowed from using slug ammo for no rational reason) with a design date when LBX autocannons are available you know you're looking at an intentionally bad design like the joke units with tank rifles.  It's okay for weapons to be obsolete.  The problem is when the setting pretends they aren't even though they obviously are. 

[RifleMech]

Trace the quote chain again.  You'll find you said:You're just meandering into crazy places where industrialmechs are important enough combat units to design weapons that are garbage on everything else including ICE powered vehicles. 

Here's the chain.

The catch is that in its era you're looking at freezers and if you can't mount an AC-5 you also aren't mounting enough stuff to use up your free sinks, which makes energy weapons a lot more efficient.  The precision bonus is nice, but you could have an ERLL doing four times as much damage and that's probably better in most cases. 

That depends on the unit though. There are units that can't mount DHSs.

I thought I addressed that.  Units that can't mount DHS also don't track heat from missiles.  A LRM-10 averages around 20% more damage than an AC-5 and more than half the time rolls twice on the location table.  An SRM-4 averages closer to the same damage as the AC-5, but usually rolls 2-3 locations.  Slightly more damage at all ranges and more crits at all ranges.  The AC-5's crit density advantage only applies to mechs, which can mount DHS.

Not really. Low Tech BattleMechs and IndustrialMechs still track heat and can't mount DHS. Also Engine Type can change if DHS are used or how they're used. An XXL Engine generates 6 heat when running. With 10 DHS included leaves 7 DHS that can be used for weapons. That changes how you'd do things.

Tracing the quote chain this is about LAC-2s.  There's damning with faint praise, and then there's invoking industrialmechs too small to mount an AC-5 as a military platform important enough to design and put into production a weapon that is bad everywhere else. 

Nope it was about units that don't mount DHS. Industrials and LowTech Mechs don't mount DHS. A Mech with a FCE or ICE is going to have to mount enough single heat sinks to deal with the heat. So that 5 ton ERLL is going to weigh 17.5 tons vs the LAC/2 at 7 tons.

The chain is about heat sinks. Not every unit can mount DHS. BattleMechs can also use ICE engines. Not every place is advanced enough or rich enough to use Fusion Engines. Not every planet has ER weapons either. They weren't even available for a long period of time. Not every unit can mount a 5 ton ERLL, 12 heat sinks and a .5 ton Power Amplifier. Even with a Fusion Engine a unit might not have the 7 tons required to mount a ERLL. A LAC/2 or LAC/5 can be installed though as they're both lighter.

Again, this is your response to my response to your response to my claim that LAC-2s stand out as bad among other autocannons.  The only justification you or anyone else provided for LAC-2s was that something doesn't have the tonnage for an AC-5 but wants to fire out to 18 hexes.  This thus assumes a mech that can't do *anything* other than run and fire its ERLL because the 5 tons for the ERLL or the LAC-2 and ammo are all it has to spare.  You're trying to move the goalposts without providing any reason why anyone should ever mount the gun in question if there's enough tonnage to mount anything else.

No movement of the goal posts on my part especially as I have said why one would mount such weapons. Not every unit has the tech or the tonnage to space for a ERLL. Or even a LL. All those heat sinks take up a lot of weight.

Yes.  If a mech has DHS and only mounts a PPC as its sole weapon it is wasting heatsinks.  Unless it's also mounting a PPC capacitor and 5 or more jumpjets or the PPC is a heavy or ER model or it's mounting stealth armor or otherwise making use of all of its heatsinks.  If it doesn't jump it's leaving heat dissipation worth 4 tons on the table.  I don't see how this is even under contention.  If you buy a year subscription to a streaming service and only use it for one week of binge watching that is also waste.

Adding more items. Goalposts?
 
You talk as if having extra heat sinking is a bad thing. I would think better to have too much than not enough.

You keep coming back to ICE.  The only real combat units that use ICE are vehicles that can never overheat at all by definition.  It is not hard to remain under 9 heat with single heatsinks.  You just have to do some simple arithmetic instead of blindly smashing the big red Alpha Strike button. 

Theirs also Fuel Cell Engines and Fission Engine, and Support Vehicle Engines of all kinds. The first two come with 1 heat sink and 5 heat sinks. SV Engines do not come with any heat sinks, even the fusion engines. If you put any LL on a unit with those engines you're going to pay in tonnage with heat sinks.

Hardly.  Impaired functionality matters.  A hit that doesn't contribute to impairing functionality because the target is too evasive for you to hit again may as well not have happened.  If you're tracking C-bills repairing armor has some cost, but because of the weight multiplier 5 points of armor cost less on a 20 ton mech than on an 80 ton mech. 

For the want of a nail the war was lost.
A single 1 point hit can be the difference between all the armor in that location being lost and an internal hit being made.

No one uses prototype endo.  Theoretically the Hegemony must have built a prototype, but it was never a deployed unit, doesn't have stats, and likely wasn't armed with anything but load simulating weights because its job was to test a skeleton not to fight.  And it's rare to run out of crits on just endo without either ferro or the really hot running ER energy weapons, which are not required to make medium autocannons look bad. 

It would have been used during the Reunification War. It was used during the War of 3039. That we don't have stats for it does not mean that it wasn't used. It means that TPTB didn't care to create any units with it. So far the majority of units using such prototype tech are in SB:Sword and Dragon. As for running out of crits it depends on the era and equipment used. 14 crits for ES, 6 for XL engines, 3x?-DHS. It's not hard to run out of crits.

Because you spend less on heatsinks you can only use where the ranges intersect you have more weaponry.  For every 1 ton of ML you aren't firing with your LRMs at 7-9 hexes with your LRMs you're saving 1.5 tons of DHS that you weren't going to use either past 9 hexes or within LRM minimum range.  That's not waste.  That's trading at an advantage.  Because of those savings you wind up with more guns.  The heatsinks you don't need if you stop firing your low efficiency long range weapons like ERPPCs or ERLLs leave the mass to mount far more higher efficiency short range weapons like MLs or, if working with clantech, cERMLs.  Such designs do the same long range damage and more short range damage than designs that attempt to sink the alpha strike. 

It still means that you can't use all your weapons. It also means that any heat from damage or heat weapons will be more of a problem.

That's why you exercise some expletive trigger discipline. 

Hard to do when you didn't have enough heat for your weapons to start with.

That a gun that does 10 damage is better than a gun that does 5 damage.  If you don't like the example blame theagent.  He's the one that proposed example mechs with a PPC and a single AC-5.  While trying to defend the AC-5 no less. 

I wouldn't say better. It does more damage but better? That'd depend on other things besides just damage.

This is irrelevant to heat bracketing weapons.  For weapon bracket heat management what matters is that heatsinks have some mass (and when relevant crits) which can be used for other things if you contrive to need fewer of them.  Yes, DHS make high heat weapons better, but that was a response to you disputing the existence of bracket heat management in the DHS era. 

Brackets don't matter if you don't have the tonnage available to mount the equipment.

The stated premises are true.  The unstated premise that this made a difference is not.  The conclusion is thus false.  (snip)

That's it.  Those are the mechs from Battledroids that have the only autocannon in the Battledroids rules.  None of them are constrained to use it by a lack of critical slots for heatsinks.  The change makes ammo bin crits more likely, but ammo bin crits are the tiebreaker that makes the PPC better than the AC-10 on mechs.  The AC-5 is worse without needing to go to a tiebreaker. 

Battledroids does not mount heat sinks in the engine. The engine comes with 10 free heat sinks but they all have crits. The example used for construction , the Merlin has 18 heat sinks. The RS for the Merlin shows 18 slots taken for heat sinks. Each of those heat sinks is vulnerable to damage. That's going to effect energy boats and bracket firers before it hurts AC boats.

Improved autocannons, unless introduced in 2370 and retconned to replace the autocannons we have, don't fix the problem because the problem for the AC-5 starts once both LRMs and SRMs exist.  The problem is worst in the SHS era because for most of the DHS era the AC-5 and AC-10 are supposed to be eclipsed by the LB-10X so it doesn't much matter if they're also eclipsed by other weapons or weapon combinations.  If you see anything with a standard autocannon (other than class 20s on aerospace units purely because they're disallowed from using slug ammo for no rational reason) with a design date when LBX autocannons are available you know you're looking at an intentionally bad design like the joke units with tank rifles.  It's okay for weapons to be obsolete.  The problem is when the setting pretends they aren't even though they obviously are.

I don't see Autocannons as inferior to Missiles. For units that track heat, Missiles generate more which means more weight, crits for heat sinks. They also don't do as much damage. You might have all of them hit, odds are though you won't. So to equal AC/s you need more missile launchers. Or they're mounted on Aerospace for a solid number. SRMs also have a shorter range. So I wouldn't say Missiles are superior. A better option depending on the unit and the era but not superior.

[massey]

What I was hoping for was an easy change that wouldn't require any more complexity, but would mollify some of the AC critics.  I didn't really want to re-hash the "PPC vs AC-5" debate, instead I wanted something that would bypass it.

Specialty ammo is cool and all, but the downside is that in a pickup game you never know which one you need.  If standard AC ammo worked as a passable anti-air and anti-infantry round, then you're never really unprepared if your opponent brings out an unusual unit type.  No, you aren't specialized against heavy armor like the PPC is, but you're a true generalist.  You could leave the weapon's stat line alone, and just by changing a handful of optional rules (that have themselves been changed several times already), you have a plausible explanation why people keep putting the damn things on Battlemechs.

Sadly, my tabletop gaming group has long disbanded since we're all old married guys now, so I don't have an opportunity to use such a suggestion.  In the event I find myself running a mechwarrior campaign (which would probably mean I had gotten divorced and was a bachelor again), I may try it.  But as far as head-canon explanations, it's probably what I'm going to go with for now.

[Hptm. Streiger]

What I was hoping for was an easy change that wouldn't require any more complexity, but would mollify some of the AC critics.  I didn't really want to re-hash the "PPC vs AC-5" debate, instead I wanted something that would bypass it.

the simplest way would be to hone the flexibility of an AC.
So you could trade to hit modifers for damage

Name	R-3	R-2	R-1	R0	R+1	R+2
LAC	-	-	1	3	-	4
MAC	-	1	3	6	7	8
HAC	1	2	5	11	12	15
AAC	2	5	10	20	22	27

yes i upgraded the base values for the 3 smaller cannons

[idea weenie]

What I wish you could do is let conventional AC use LB-X ammo, but the LB-X autocannons can use a variable choke setting.  The tighter the choke, the more damage you deliver, but the looser the choke, the more likely to get the to-hit bonus.

Examples, assuming all the shots hit:
AC/5 fires standard ammunition, and does one hit of 5 pts of damage
AC/5 fires LB-X ammunition, rolls on the cluster table, and on average does three hits of 1-pt each

LB-X-5 fires in full choke mode, doing a single hit of 5 pts of damage (no cluster rolls or to-hit modifier, since it is over 1/2 the AC base damage)
LB-X-5 fires in 3-pt choke mode, doing one hit of 3 pts, and one hit of 2 pts of damage (no cluster rolls since the choke mode is greater than half the AC base damage)
LB-X-5 fires in 2-pt choke mode, doing two hits of 2 pts each, and one hit of 1 pt of damage (it does roll on the cluster table since it is less than half the AC base damage, but the choke setting it is more than 1/4 the AC base damage meaning it does not get the bonus to-hit)
LB-X-5 fires in no choke mode, doing five hits of 1 pt of damage each (it does roll on the cluster table for number of projectile that hit, but gets the 1 pt targeting bonus since the choke is less than 1/4 the AC base damage)

But for existing AC, I would want to reduce the mass of the smaller autocannons (AC/2 and AC/5).  Maybe AC/10?

***

Another idea could be putting some ammunition as on-mount instead of storing in ammo bays.  On-mount ammunition cannot be used by other autocannons, but does not need a critical slot.  The down side is that if the autocannon gets a critical hit, there should be a chance for the on-mount ammunition to be destroyed.

Now to figure the max amount of ammunition can be stored on-mount.  Maybe weapon mass/4, rounded down to quarter tons?  So an AC massing 5 tons could store up to 1.25 tons of ammunition on-mount.  That ammunition could only be used by that autocannon, or it can be dumped over the side (in case the armor is getting thin).  If the Mech stores 2 tons of ammunition, the remaining .75 tons is stored in a critical slot and is subject to normal ammunition explosion rules.

[RifleMech]

What I was hoping for was an easy change that wouldn't require any more complexity, but would mollify some of the AC critics.  I didn't really want to re-hash the "PPC vs AC-5" debate, instead I wanted something that would bypass it.

Specialty ammo is cool and all, but the downside is that in a pickup game you never know which one you need.  If standard AC ammo worked as a passable anti-air and anti-infantry round, then you're never really unprepared if your opponent brings out an unusual unit type.  No, you aren't specialized against heavy armor like the PPC is, but you're a true generalist.  You could leave the weapon's stat line alone, and just by changing a handful of optional rules (that have themselves been changed several times already), you have a plausible explanation why people keep putting the damn things on Battlemechs.

Sadly, my tabletop gaming group has long disbanded since we're all old married guys now, so I don't have an opportunity to use such a suggestion.  In the event I find myself running a mechwarrior campaign (which would probably mean I had gotten divorced and was a bachelor again), I may try it.  But as far as head-canon explanations, it's probably what I'm going to go with for now.

Thing about specialty ammo is you never know what you need until you've engaged the enemy. You can make some educated guesses knowing your opponents armor preferences but its still a guess.

What I wish you could do is let conventional AC use LB-X ammo, but the LB-X autocannons can use a variable choke setting.  The tighter the choke, the more damage you deliver, but the looser the choke, the more likely to get the to-hit bonus.

Examples, assuming all the shots hit:
AC/5 fires standard ammunition, and does one hit of 5 pts of damage
AC/5 fires LB-X ammunition, rolls on the cluster table, and on average does three hits of 1-pt each

LB-X-5 fires in full choke mode, doing a single hit of 5 pts of damage (no cluster rolls or to-hit modifier, since it is over 1/2 the AC base damage)
LB-X-5 fires in 3-pt choke mode, doing one hit of 3 pts, and one hit of 2 pts of damage (no cluster rolls since the choke mode is greater than half the AC base damage)
LB-X-5 fires in 2-pt choke mode, doing two hits of 2 pts each, and one hit of 1 pt of damage (it does roll on the cluster table since it is less than half the AC base damage, but the choke setting it is more than 1/4 the AC base damage meaning it does not get the bonus to-hit)
LB-X-5 fires in no choke mode, doing five hits of 1 pt of damage each (it does roll on the cluster table for number of projectile that hit, but gets the 1 pt targeting bonus since the choke is less than 1/4 the AC base damage)

But for existing AC, I would want to reduce the mass of the smaller autocannons (AC/2 and AC/5).  Maybe AC/10?

***

Another idea could be putting some ammunition as on-mount instead of storing in ammo bays.  On-mount ammunition cannot be used by other autocannons, but does not need a critical slot.  The down side is that if the autocannon gets a critical hit, there should be a chance for the on-mount ammunition to be destroyed.

Now to figure the max amount of ammunition can be stored on-mount.  Maybe weapon mass/4, rounded down to quarter tons?  So an AC massing 5 tons could store up to 1.25 tons of ammunition on-mount.  That ammunition could only be used by that autocannon, or it can be dumped over the side (in case the armor is getting thin).  If the Mech stores 2 tons of ammunition, the remaining .75 tons is stored in a critical slot and is subject to normal ammunition explosion rules.

There is the fluff ammo for the Partisan AA Tank. Functions as normal against ground targets and Flak against Aircraft. It wouldn't be too hard to make it work against infantry too.

What I wish you could do is let conventional AC use LB-X ammo, but the LB-X autocannons can use a variable choke setting.  The tighter the choke, the more damage you deliver, but the looser the choke, the more likely to get the to-hit bonus.

That sounds complicated. How about a -? on the cluster chart for the standard AC? That way they wouldn't be better than LB-Xs.

Another idea could be putting some ammunition as on-mount instead of storing in ammo bays.  On-mount ammunition cannot be used by other autocannons, but does not need a critical slot.  The down side is that if the autocannon gets a critical hit, there should be a chance for the on-mount ammunition to be destroyed.

Now to figure the max amount of ammunition can be stored on-mount.  Maybe weapon mass/4, rounded down to quarter tons?  So an AC massing 5 tons could store up to 1.25 tons of ammunition on-mount.  That ammunition could only be used by that autocannon, or it can be dumped over the side (in case the armor is getting thin).  If the Mech stores 2 tons of ammunition, the remaining .75 tons is stored in a critical slot and is subject to normal ammunition explosion rules.

On Mount? Do you mean externally or you do mean giving AC's get a free amount of ammo? Either's okay with me but I think a quarter of the weapons weight is a bit much. That'd give the AC/20 3.5 tons of free ammo. That would change Mechs like the Hunchback IIC as it'd have 3 tons per UAC/20 free before ammo in the bay. The Rifleman wouldn't be low on ammo either as it'd have a total of 5 tons of ammo. I know the point is to make AC/s better but I think that's overdoing it. I can see a quarter of a ton rounded down of ammo being free. Kind of hot loading the AC. That way the Rifleman would have 5 extra rounds per gun. It's still low on ammo but it would last a bit longer and the Hunchback IIC is still a last shot at honor/suicide machine.


edit
After thinking about it for a bit, I think going by weight of the weapon opens the door to munchkinism. For example, you could eliminate the Marauder's ammo bomb and still double the amount of ammo the AC/5 has.

[Daryk]

I like the choke idea!  :thumbsup:

Just to be clear, you're saying normal ACs firing cluster ammo have no choke, right?  ???

[Hptm. Streiger]

After thinking about it for a bit, I think going by weight of the weapon opens the door to munchkinism. For example, you could eliminate the Marauder's ammo bomb and still double the amount of ammo the AC/5 has.

This amount of rounds, than yes. However a couple of rounds might be ok.
Although as you said munchkin might drop the AC2 rounds on the BlackJack and are ok with say even 20 rounds per gun - so it could not be a fixed value like half a ton worth of ammunition.

Instead, you could say you get 20% per ton of ammunition for free no matter how many guns you deploy... so the KGC gets 2 rounds free, the Atlas as well. BlackJack gets 9 rounds extra... and so on.

 or alternatively remove the extra criticals for some ammunition when you mount a AC. (unless its the AC2), in general storing the ammunition near to the weapon would be a great fix for all ammunition dependend systems.

[idea weenie]

That sounds complicated. How about a -? on the cluster chart for the standard AC? That way they wouldn't be better than LB-Xs.

The choke on LB-X would be to allow it to fire the pellets as different sized clumps.  Full choke from an LB-X-20 would be almost all pellets being aimed at a single location on an enemy Mech.  You don't get the bonus to-hit from any spread, but you also shouldn't have to worry about rolling snake eyes on the cluster chart.

Perhaps 3 scales for each autocannon (well, only 2 for the LB-X-2):

• Full choke - no to-hit bonus, no roll on the cluster chart, and only hit the selected location.  Treat like a single hit of the autocannon's value
• Partial choke - you get the to-hit bonus, while rolling d6+3 on cluster table, and the hit locations have to be adjacent to each other.  More reliable damage than no choke, while more accurate than full choke
• No choke would be getting the 1 pt bonus to hit, while rolling 2d6 on the cluster table, and hit locations can be anywhere.  For when you need to sandpaper someone

For regular autocannons, the penalty on the cluster chart does make better sense than getting the same benefit as LB-X.  To me the regular AC was designed for firing solid shells, and shotgun slugs would be an ammo change for a weapon that was not originally designed for it.  LB-X was designed from the beginning to exploit the capabilities of the shotgun-style ammunition

On Mount? Do you mean externally or you do mean giving AC's get a free amount of ammo? Either's okay with me but I think a quarter of the weapons weight is a bit much. That'd give the AC/20 3.5 tons of free ammo. That would change Mechs like the Hunchback IIC as it'd have 3 tons per UAC/20 free before ammo in the bay. The Rifleman wouldn't be low on ammo either as it'd have a total of 5 tons of ammo. I know the point is to make AC/s better but I think that's overdoing it. I can see a quarter of a ton rounded down of ammo being free. Kind of hot loading the AC. That way the Rifleman would have 5 extra rounds per gun. It's still low on ammo but it would last a bit longer and the Hunchback IIC is still a last shot at honor/suicide machine.

edit
After thinking about it for a bit, I think going by weight of the weapon opens the door to munchkinism. For example, you could eliminate the Marauder's ammo bomb and still double the amount of ammo the AC/5 has.

It would not be free ammo, you still have to pay in tonnage, C-Bills, and BV.  The only advantage is that you could save a critical slot if the amount of ammo carried is small enough.  So if the weapon is 2 tons, and you want to carry half a ton of ammo, the ammo could all be listed as on-mount, and you don't need to allocate a critical slot for the ammo.  If you were carrying a full ton of ammo, only a half ton could be carried on-mount, but the remaining half ton would need a critical slot.

I would like to include another limit where on-mount ammo is for that weapon only, and cannot be shared with other guns.  So the Marauder with a single AC/5 would not care, but a Piranha with 12 Machine Guns might want to think twice about putting as much ammo as possible on-mount.

You are right, the on-mount would need some other upper limit than 25% of weapon mass.

I like the choke idea!  :thumbsup:

Just to be clear, you're saying normal ACs firing cluster ammo have no choke, right?  ???

Exactly right.  Regular AC are designed for firing regular ammunition, so if a choke is on the gun and the choke gets hit, the regular ammo could not be fired.  Rifleman's idea above about the penalty on the cluster chart would also reflect a gun trying to use different ammunition than what was originally designed.

[RifleMech]

This amount of rounds, than yes. However a couple of rounds might be ok.
Although as you said munchkin might drop the AC2 rounds on the BlackJack and are ok with say even 20 rounds per gun - so it could not be a fixed value like half a ton worth of ammunition.

Instead, you could say you get 20% per ton of ammunition for free no matter how many guns you deploy... so the KGC gets 2 rounds free, the Atlas as well. BlackJack gets 9 rounds extra... and so on.

 or alternatively remove the extra criticals for some ammunition when you mount a AC. (unless its the AC2), in general storing the ammunition near to the weapon would be a great fix for all ammunition dependend systems.

I used 25% of the ammo but 20% would work too. It does help smaller ACs but not so much that I'd go without ammo. It just means I can take more shots I might not otherwise.  I'd still go per gun as it'd be easier and make more sense than per design. That ends up being more math and nerfs designs with more ACs. I'd also require at least a ton of ammo but I think that's in the rules any way. We can't preven't people from leaving the bins empty but we can't make them wish they'd loaded them.  >:D

If I were to do this I'd apply it to all AC types and Rifle Cannons.

That does make better sense.  To me the regular AC was designed for firing solid shells, and shotgun slugs would be an ammo change for a weapon that was not originally designed for it

Cool :
I'm not sure about which weapon is designed for what as there'd different ammo in the fluff before the LB-X was introduced. Once it did seem that the LB-X was the shotgun to the AC/s rifle but that's changed. Now it just seems like the LB-X is an improved AC with a limited selection in ammo types.

 Should the -# on the cluster hit chart increase with the size of the AC or just be a single number?

It would not be free ammo, you still have to pay in tonnage, C-Bills, and BV.  The only advantage is that you could save a critical slot if the amount of ammo carried is small enough.  So if the weapon is 2 tons, and you want to carry half a ton of ammo, the ammo could all be listed as on-mount, and you don't need to allocate a critical slot for the ammo.  If you were carrying a full ton of ammo, only a half ton could be carried on-mount, but the remaining half ton would need a critical slot.

I would like to include another limit where on-mount ammo is for that weapon only, and cannot be shared with other guns.  So the Marauder with a single aC/5 would not care, but a Piranha with 12 machine guns might want to think twice about putting as much ammo as possible on-mount.

You are right, the on-mount would need some other upper limit than 25% of weapon mass.

So it's more like weapons on small vehicles? The ammo is included in with the weapon for critical slots.

Cool :)  I think ammo would work. I'm not sure what else might.

[Daryk]

I think adding the choke to the LB-Xs keeps them more than "better enough" than regular ACs, though I'll say I also support allowing LB-Xs to fire alternative ammo...  Ultras I'm less sure of, but honestly, why not?

[idea weenie]

I used 25% of the ammo but 20% would work too. It does help smaller ACs but not so much that I'd go without ammo. It just means I can take more shots I might not otherwise.  I'd still go per gun as it'd be easier and make more sense than per design. That ends up being more math and nerfs designs with more ACs. I'd also require at least a ton of ammo but I think that's in the rules any way. We can't preven't people from leaving the bins empty but we can't make them wish they'd loaded them.  >:D

If I were to do this I'd apply it to all AC types and Rifle Cannons.

I originally went with 25% because it made the math easy (quarter tons, instead of fractional accounting for .2, .4, .6, and .8 that would result from 20% of weapon mass).

Cool :
I'm not sure about which weapon is designed for what as there'd different ammo in the fluff before the LB-X was introduced. Once it did seem that the LB-X was the shotgun to the AC/s rifle but that's changed. Now it just seems like the LB-X is an improved AC with a limited selection in ammo types.

Should the -# on the cluster hit chart increase with the size of the AC or just be a single number?

I'd prefer if the number was a constant, to make a lot less need to look up on a table vs a per-weapon penalty.  If autocannons are rifled, would there be a greater penalty based on range bracket?

In this fan rule, ACs were found to have the ability to fire LB-X shells, while the LB-X autocannons were designed from the beginning to use shotgun-style ammunition?

So it's more like weapons on small vehicles? The ammo is included in with the weapon for critical slots.

Cool :)  I think ammo would work. I'm not sure what else might. 

To me ammunition would be the only thing that could work.  Everything else would require its own system.  I hope I am wrong, and more ideas come up


Of course now I am thinking of integrated systems, where you save on critical slots, but lose out on tonnage or effectiveness.  (i.e. heat sinks dump more heat, but only for the weapon they are linked to; or targeting computers fit into the weapon's crannies needing fewer critical slots, but require more tonnage since they are calculated on a per-weapon basis rather than total tonnage of appropriate weapons)

[RifleMech]

I think adding the choke to the LB-Xs keeps them more than "better enough" than regular ACs, though I'll say I also support allowing LB-Xs to fire alternative ammo...  Ultras I'm less sure of, but honestly, why not?

I don't know if chokes on guns are a real think or not but it sounds dangerous to me. Even if it isn't, I think it'd be complicated to implement and use. Allowing LB-Xs to use other ammo though I got zero problem with. Ultras... why not?

I originally went with 25% because it made the math easy (quarter tons, instead of fractional accounting for .2, .4, .6, and .8 that would result from 20% of weapon mass).

I'd prefer if the number was a constant, to make a lot less need to look up on a table vs a per-weapon penalty.  If autocannons are rifled, would there be a greater penalty based on range bracket?

In this fan rule, ACs were found to have the ability to fire LB-X shells, while the LB-X autocannons were designed from the beginning to use shotgun-style ammunition?

To me ammunition would be the only thing that could work.  Everything else would require its own system.  I hope I am wrong, and more ideas come up


Of course now I am thinking of integrated systems, where you save on critical slots, but lose out on tonnage or effectiveness.  (i.e. heat sinks dump more heat, but only for the weapon they are linked to; or targeting computers fit into the weapon's crannies needing fewer critical slots, but require more tonnage since they are calculated on a per-weapon basis rather than total tonnage of appropriate weapons)

That's cool. I just got a lot of free ammo that way. That's why I used 25% on the amount of ammo instead.

Thing is with a flat number between all the autocannons a Jackrabbit gets 11 rounds for its AC/2. A Blackjack would get only 5 for each. A Mech with 4 would get 2. The Hunchback IIC wouldn't get any extra ammo since you can't split that 1 extra shot. On the other hand if its a flat % of the ammo its easier to figure out and every AC/ benefits.

I don't think rifling would add much to range. Maybe a little but I think it'd make the weapon more accurate. I'm not sure how much it helps bigger weapons like cannons either.

Should extra ammo be given to MGs, Gauss Weapons, and Chemical Lasers?

If it were me, I'd allow but the AC and the LB-X to fire all kinds of ammo. The LB-X just does it better at longer ranges. I'd also change the ammo so cluster rounds are more like shot rounds. They inflict more damage up close and less further away because of the shot spreading out but the spread does increase the chance of a hit further out. The LB-X "cluster" rounds wouldn't really change but would be made clear that they're timed proximity rounds that explode when near the target. I'd also let LB-X rapid fire standard rounds at least. Of course if it were up to me, the Partisan AA Tank's ammo would be available too.

So far I haven't thought of anything better. Ammo still seems the best option.

I did toy with having some weapons be more "externally" mounted so they take less crits but are outside the armor and more vulnerable to hits. I never got to test it though. I still like the older targeting computer rules too so I could have a computer on just a few weapons instead of all.

[Atarlost]

I think adding the choke to the LB-Xs keeps them more than "better enough" than regular ACs, though I'll say I also support allowing LB-Xs to fire alternative ammo...  Ultras I'm less sure of, but honestly, why not?

LBX cluster rounds aren't shot shells they're proximity fused fragmentation rounds.  The ones that spread like shotguns are HAGs with their cluster bonus shifting by range bracket. 

[Hptm. Streiger]

LBX cluster rounds aren't shot shells they're proximity fused fragmentation rounds.  The ones that spread like shotguns are HAGs with their cluster bonus shifting by range bracket.

And those are described as small caliber GR with high rate of fire developed from the AP Gauss.
In the end it's your head-canon

[Atarlost]

And those are described as small caliber GR with high rate of fire developed from the AP Gauss.
In the end it's your head-canon

HAGs are indeed more like volley guns thanshotguns, but they have projectiles diverging in a cone from the weapon like a shotgun.  LBX cluster rounds don't diverge in a cone from the weapon.  They fire explosive cluster rounds.  Cluster means the projectiles spread out from a single munition at the target.  When it diverges from the weapon it's called Canister. 

[Daryk]

I took the mention of a choke to be a "choke", not a literal one.  I think the game mechanical effect would be interesting.

[Col Toda]

I agree with  Cannonshop useful enough as is . We are starting to see infantry field guns and any alteration to them would just make it more gross . Be it a platoon shooting 2or 3?  AC /2 s dug in ,with a heavy woods hex or 1 or 2 ? HVAC/10 s . Dug in -2 , heavy woods -2 long range -4 so -8 total for the HVACS add smoke-1 ,when thet fire . That is as is.

[Retry]

I agree with  Cannonshop useful enough as is . We are starting to see infantry field guns and any alteration to them would just make it more gross . Be it a platoon shooting 2or 3?  AC /2 s dug in ,with a heavy woods hex or 1 or 2 ? HVAC/10 s . Dug in -2 , heavy woods -2 long range -4 so -8 total for the HVACS add smoke-1 ,when thet fire . That is as is.

"They're useful as long as you use it on a unit type that intentionally neglects all the traditional disadvantages of said weapon type for no reason" is kind of the point.