Tell me about the Light AC-2

[Atarlost]

First off, I apologize if this is the wrong place.  I see similar threads in articles but I'm not sure why they go here so I'm also not sure of the exact criteria. 

I've seen people speak favorably of the light  AC-2, particularly in a design thread about retconning availability D components into the lostech era.  I just can't see why. 

The AC-2 and AC-5 are generally considered the worst weapons in lostech era play, much less the era the LACs are actually available in.  They give up the range that was the sole niche of the AC-2 while having worse damage efficiency than the AC-5 (2 LAC-2s weigh the same as a single AC-5 and go through ammo at approximately the same rate and put out more heat where applicable while doing only 80% of the damage).  Unlike the similar comparison between AC-5s and PPCs, the LAC-2 lacks the saving grace of the AC-5 because the it's being compared to something with exactly the same advanced ammo options.

So what's the niche and why is it worth not using something with better general stats? 

[The Eagle]

I'll presage my response with the caveat that I've never used either of them.  That being said, my understanding is that LACs decrease the mass of the weapons (a big complaint, given their mass-to-damage ratio) while still allowing the use of variant ammunition (such as precision or armor piercing),  which was previously restricted to just regular stock autocannons.

[UnLimiTeD]

If you want to use autocannons, why not these.
Sure, they are short ranged, and the damage is absolutely pitiful, but if you already decided to accept that...
Though, yes, I'd prefer regular AC/2s and LAC/5s.
The AP-Ammo is poor on smaller calibres, and for AA applications, range is a significant consideration.

[Caedis Animus]

The AC-2 and AC-5 are generally considered the worst weapons in lostech era play, much less the era the LACs are actually available in.  They give up the range that was the sole niche of the AC-2 while having worse damage efficiency than the AC-5 (2 LAC-2s weigh the same as a single AC-5 and go through ammo at approximately the same rate and put out more heat where applicable while doing only 80% of the damage).  Unlike the similar comparison between AC-5s and PPCs, the LAC-2 lacks the saving grace of the AC-5 because the it's being compared to something with exactly the same advanced ammo options.

I'd rather use the twin LAC-2s for some alternate ammo types, namely AP.

[HobbesHurlbut]

I'd rather use the twin LAC-2s for some alternate ammo types, namely AP.

I rather have Precision and turn the twin LAC-2 into annoying harassment weapons.

[Scotty]

The Light AC/2 is complete garbage.  If the range were closer to 7/14/21 it might be worth using, but as is it's four tons for a longer ranged Machine Gun with gimmick ammo that doesn't actually do much because even a Wasp laughs at two points of damage.

If you want to run two of these don't bother, just use a RAC/2 instead.  And RAC/2s aren't that great either.

[ThePW]

The only benefit that I can think of for using the Light Series of AC's is the weight savings. replacing the twin AC/2's on a CLNT-2-4T Clint with a pair of LAC/2's give back 4 tons. That paper thin 4.5 tons of armor suddenly becomes 8.5 tons. Another thing to consider if, for campaign play, if all you have on hand is Lvl-1 units, replacing any AC/2 & AC/5 with a LAC version now, technically, gives you units that raise your tech level (and the funding) for Chaos Campaign warchest points purposes...


but other than side, incidentals, there is very little meta game reasons to use a LAC over, say the RAC's for example...

[Sabelkatten]

The LAC/5 with precision ammo is actually pretty good. Two of them plus 3 tons ammo and a DHS are 14 tons, which is the same as a LXPL with similar performance.

The LAC/2 is however crap. You save about 25% of the weight and get 20% more range, but you loose 60% of the damage!

[mbear]

Light AC/2 = SRM-1 with twice the range.

Yes, they suck for 'Mechs and vehicles, but you can have seven of them attached to an infantry platoon. That gives you an SRM-7 with the range of a PPC.

[Kit deSummersville]

If you want to run two of these don't bother, just use a RAC/2 instead.  And RAC/2s aren't that great either.

The ER SRM-6 is handy for scavengers culling the injured members of the pack.

[packhntr]

The ER SRM-6 is handy for scavengers culling the injured members of the pack.

ER SRM-6 ??????

[Kit deSummersville]

ER SRM-6 ??????

The RAC/2 is an ER SRM-6. Or-5. Or -4, etc.

[packhntr]

The RAC/2 is an ER SRM-6. Or-5. Or -4, etc.

AH...ok.....yeah, I can see it like that. 

[packhntr]

Honestly, the LAC2 isn't that great of a weapon by itself.  Used in mass.....that's another story.  However, they still weigh a lot for the damage they can do and now with the reduced range, I'd rather take a RAC-2 or 5...or a standard large laser.  To heavy, too little damage, and now too short of range. 

[UnLimiTeD]

If aiming for long range crit seeking, you might as well take actual missiles, though.
Say, 4 lrm 5 for the weight of 2 LAC/2. On a vehicle, the extra heat isn't a concern, either.

[Atarlost]

I'd rather use the twin LAC-2s for some alternate ammo types, namely AP.

The math doesn't really support this.  AC-2s firing AP ammo suffer a -4 rolling on the number of crits table, meaning they need a 12.  AC-5s suffer a -3 allowing them to also score an actual crit on an 11.  The LACs have a small advantage from having two chances to roll 12 on the location chart, but I suspect that an LB-5X that has a relative -2 to hit and averages three rolls on the location chart is going to crit more than either in practice. 

The only benefit that I can think of for using the Light Series of AC's is the weight savings. replacing the twin AC/2's on a CLNT-2-4T Clint with a pair of LAC/2's give back 4 tons.

You can get the same weight savings centuries earlier by swapping them for a single AC-5.  You're giving up the whole point of having a CLNT-2-4T in the first place, though.  If the range wasn't important to you you should have converted it to a CLNT-1-2R or CLNT-2-3T long before the LAC-2 was invented.   

Light AC/2 = SRM-1 with twice the range.

Yes, they suck for 'Mechs and vehicles, but you can have seven of them attached to an infantry platoon. That gives you an SRM-7 with the range of a PPC.

Or you could have 3 RAC-2s Even with the cluster rolls you can expect to average about 70% more clusters on target.  And how likely are you to get to use the functionally unlimited ammo of the LAC-2s on an infantry platoon?  Remember, field guns don't have to roll for jamming.  Unlike on a tank where firing a RAC at full RoF is likely to mean you don't have it the next round or possibly more depending on your unjamming rolls, as a field gun it just works with no downside except rapid ammunition use. 

[Hellraiser]

The Light AC/2 is complete garbage.  If the range were closer to 7/14/21 it might be worth using, but as is it's four tons for a longer ranged Machine Gun with gimmick ammo that doesn't actually do much because even a Wasp laughs at two points of damage.

If you want to run two of these don't bother, just use a RAC/2 instead.  And RAC/2s aren't that great either.

I really don't think 6-12-18 w/ 0 minimum is a bad range  (I think that is the LAC range off the top of my head)

1 Less than LRM Range & the Same as AC5 range all w/o any minimum.

Not horrid for a -2 Precision weapon.

Certainly not the best use of 5 tons but not horrible as an option on something like a Warrior, Scorpion, Vedette, Blackjack, or Vulcan.

[Colt Ward]

I think this needs to be answered in two ways . . .

For the 3025 retcon (which I agree with and should include normal RLs and maybe LPPCs) . . . as someone said, they are a great fit on the light and medium mechs already using AC/2s since they will as someone noted give you more tonnage to play with for a low-heat option.  It also has a favorable short & med range bracket . . .

For 3050+ . . . well, I like the rapid fire rules for old ACs which LACs qualify for . . . IMO it makes things like the Scorpion & Vedette more worthwhile.  The LAC/2 would be good for a AA tank using flak, but we do not get it afaik.  AP ammo is blah . . . Precision . . . well, here it makes some sense IMO again for light & med mechs (or tanks!).

[Atarlost]

I think this needs to be answered in two ways . . .

For the 3025 retcon (which I agree with and should include normal RLs and maybe LPPCs) . . . as someone said, they are a great fit on the light and medium mechs already using AC/2s since they will as someone noted give you more tonnage to play with for a low-heat option.  It also has a favorable short & med range bracket . . .

You're just repeating that they're great, but AC-5s are also 3025 tech and are better.  And even AC-5s are very niche when the only useful specialty ammo is flak.  Unless you're AA you should have been using energy weapons or missiles.  If you're AA the range of the full size AC-2 was actually valuable because there are VTOLs that can fire from outside LAC-2 range, but not full size AC-2 range. 

There is no benefit to a low heat option if it's heavier than a high heat option and enough heatsinks to make up the difference.  Two LAC-2, two SHS, and a ton of ammo come to 11 tons.  Two LRM-5s, four SHS, two tons of ammo, and a medium laser also come to 11 tons.  The latter is just better unless you're so packed with endosteel and ferro-fibrous armor you can't find the crits.  In 3025 that's not an issue. 

For 3050+ . . . well, I like the rapid fire rules for old ACs which LACs qualify for . . . IMO it makes things like the Scorpion & Vedette more worthwhile.  The LAC/2 would be good for a AA tank using flak, but we do not get it afaik.  AP ammo is blah . . . Precision . . . well, here it makes some sense IMO again for light & med mechs (or tanks!).

Again, why aren't you using an AC-5?  If you're using rapid fire rules they apply to it too.  It can use flak or precision ammo just as well. 

[Scotty]

Again, why aren't you using an AC-5?  If you're using rapid fire rules they apply to it too.  It can use flak or precision ammo just as well.

The AC/5 is garbage, that's why.  Even in 3025.  Granted, all the reasons why hypothetical LACs in 3025 make the AC/5 even more garbage all have to do with the LAC/5 and not the LAC/2.  The LAC/2 is still pretty pointless.

In some ways a single LAC/2 is superior to the AC/5, though, especially if you're just using it for flak.  Flak isn't for VTOLs, it's for ASFs, and ASFs don't care how big the hit is, they just care that they've been hit in the first place to prompt a lawn dart check.  The extra four tons left over is the major advantage.  Putting on two of them is just a waste.

[Arkansas Warrior]

The AC/5 is garbage, that's why.  Even in 3025.  Granted, all the reasons why hypothetical LACs in 3025 make the AC/5 even more garbage all have to do with the LAC/5 and not the LAC/2.  The LAC/2 is still pretty pointless.

In some ways a single LAC/2 is superior to the AC/5, though, especially if you're just using it for flak.  Flak isn't for VTOLs, it's for ASFs, and ASFs don't care how big the hit is, they just care that they've been hit in the first place to prompt a lawn dart check.  The extra four tons left over is the major advantage.  Putting on two of them is just a waste.

Doesn’t the 6 hexes of range you lose matter rather a lot for AAA purposes, though?

[Colt Ward]

You're just repeating that they're great, but AC-5s are also 3025 tech and are better.  And even AC-5s are very niche when the only useful specialty ammo is flak.  Unless you're AA you should have been using energy weapons or missiles.  If you're AA the range of the full size AC-2 was actually valuable because there are VTOLs that can fire from outside LAC-2 range, but not full size AC-2 range. 

There is no benefit to a low heat option if it's heavier than a high heat option and enough heatsinks to make up the difference.  Two LAC-2, two SHS, and a ton of ammo come to 11 tons.  Two LRM-5s, four SHS, two tons of ammo, and a medium laser also come to 11 tons.  The latter is just better unless you're so packed with endosteel and ferro-fibrous armor you can't find the crits.  In 3025 that's not an issue. 

Again, why aren't you using an AC-5?  If you're using rapid fire rules they apply to it too.  It can use flak or precision ammo just as well.

First off, I would never put in 2t of ammo for 2 AC/2 in 3025 and not for 2 AC/2 or LAC/2 in 3050+ -a single ton will do, I doubt what I was suggesting in a 30-40t design would last 22 or 11 rounds of fire (supposing Prec for 3050+)- of course I would also not give 2 LRM5s a second ton of ammo either for most conditions.  I am not sure why you are comparing the 2 LRM5s and a ML to the 2 LAC/2 that are heat neutral since the LRM set would not be . . . but its also not like it matters on most 3025 40t and under designs, rarely do they need more sinks.  IMO, four things your LRM scenario is overlooking . . . the LACs will not have the minimum range problems the LRMs will have- in fact, their short range is where the LRMs start adding to their numbers. 

Also, either 1 ton of ammo or your 2, the LACs will have nearly double the battlefield endurance.  Might be too much but honestly a pair of LAC/2s are going to be 'fire every turn, so what its a 12.' 

Third you do get a couple of scenario situations where missiles are messed up but ACs are not. 

Finally, 'LRM5s are superior for everything at range, MLs are up close' exploits some known situations (3 LRM5s weight less than a LRM15) and is boring.  If you want to spam LRM5s, be my guest but you were asking about situations were a LAC/2 could make some sense so . . .

Take a hypothetical 3025 variant someone suggested, the Clint 2-3T . . . swap that AC/5 for a LAC/2 and you have cut the weight of the gun down by 4t.  Which is a LOT you could add to that design . . . you could max the armor (52% sq), add a few heat sinks so it could jump and alpha w/ 1t for armor, you could replace the CT ML with a Large Laser if you wanted to, or quite a few other possibilities.  But now that fast low weight medium has a bit more to it while keeping a ranged plink'ing harasser.

For a 3050 option . . . no longer does it really work on a light mech with the introduction of DHS, just too easy to put a ERLL like the Spider or a ERPPC like a Razorback.  To me it becomes a cheap ranged vehicle/speedster hunter . . . you can take a bog standard 3025 Scimitar, pull the AC/5 and put 2 LAC/5 with a single ton of ammo and get slightly more salvos- 11 if using precision.  Move about the battlefield and plink at the heavy/assault armor or damaged mechs for relatively low BV, precision just allows it to hunt its counterparts better.

AW- nearest point in the flight path

[Scotty]

Doesn’t the 6 hexes of range you lose matter rather a lot for AAA purposes, though?

An AC/5 and a LAC/2 have the same maximum range.  The comparison presented was to the AC/5.

[Caedis Animus]

The math doesn't really support this.  AC-2s firing AP ammo suffer a -4 rolling on the number of crits table, meaning they need a 12.  AC-5s suffer a -3 allowing them to also score an actual crit on an 11.  The LACs have a small advantage from having two chances to roll 12 on the location chart, but I suspect that an LB-5X that has a relative -2 to hit and averages three rolls on the location chart is going to crit more than either in practice. 

If I had access to an LB5X, it's a no-brainer to take that instead-but less for crits and more for sheer versatility. I was assuming the choice was bog-standard AC/5 versus twin LAC-2s. As for why I'd rather use 2xLAC2 with AP over 1xAC5 with AP, it's more of a comfort thing; Even if the margin for success is higher for the AC5 on a single roll, it's still just one chance versus two.

In other words, I'd rather have two slightly smaller chances than a single slightly bigger one.

[Sabelkatten]

If I had access to an LB5X, it's a no-brainer to take that instead-but less for crits and more for sheer versatility. I was assuming the choice was bog-standard AC/5 versus twin LAC-2s. As for why I'd rather use 2xLAC2 with AP over 1xAC5 with AP, it's more of a comfort thing; Even if the margin for success is higher for the AC5 on a single roll, it's still just one chance versus two.

In other words, I'd rather have two slightly smaller chances than a single slightly bigger one.

3 times bigger (3 in 36 instead of 1 in 36)...

Fun note: If you count pilot damage as equal to critical hits (which is a fair comparison IMHO) then AC ammo increases the number of criticals by ~62%.

The +1 TN penalty of AP ammo means you'll be causing more criticals firing standard ammo at TN 9 (67% more hits). If you're firing Precision ammo against a TMM+2 target TN6 (before either modifier) gets you better results!

[UnLimiTeD]

I am not sure why you are comparing the 2 LRM5s and a ML to the 2 LAC/2 that are heat neutral since the LRM set would not be . .
 . . . the LACs will not have the minimum range problems the LRMs will have- in fact, their short range is where the LRMs start adding to their numbers. 

I think that was kind of the point here;
The LRMs allow slightly better range and more damage compared to LACs, and their reduced weight is such that not only can you add the required extra heatsinks, you also have space for a medium laser to fire instead of the missiles if the fighting gets too close.
Of course, that ignores Flak Ammo, but for a pure "lots of hits at decent distances approach", the lrms have merit.
Yes, it might be cheesy to stack many lrm 5s, but compared to many small ACs the approach is similar.

[Atarlost]

First off, I would never put in 2t of ammo for 2 AC/2 in 3025 and not for 2 AC/2 or LAC/2 in 3050+ -a single ton will do, I doubt what I was suggesting in a 30-40t design would last 22 or 11 rounds of fire (supposing Prec for 3050+)- of course I would also not give 2 LRM5s a second ton of ammo either for most conditions.  I am not sure why you are comparing the 2 LRM5s and a ML to the 2 LAC/2 that are heat neutral since the LRM set would not be . . . but its also not like it matters on most 3025 40t and under designs, rarely do they need more sinks.  IMO, four things your LRM scenario is overlooking . . . the LACs will not have the minimum range problems the LRMs will have- in fact, their short range is where the LRMs start adding to their numbers. 

Also, either 1 ton of ammo or your 2, the LACs will have nearly double the battlefield endurance.  Might be too much but honestly a pair of LAC/2s are going to be 'fire every turn, so what its a 12.' 

You did not read the comparison correctly. 

The LAC-2s have 45 total shots.  The LRMs have 48 total shots.  Both sets proposed are heat neutral as long as the ML is not fired with the LRMs. 

Third you do get a couple of scenario situations where missiles are messed up but ACs are not. 

In 3025?  I don't think anyone suggested porting AMS to the lostech era. 

Finally, 'LRM5s are superior for everything at range, MLs are up close' exploits some known situations (3 LRM5s weight less than a LRM15) and is boring.  If you want to spam LRM5s, be my guest but you were asking about situations were a LAC/2 could make some sense so . . .

Your personal aversion to good weapons does not make the LAC-2 make sense.  If you can't tolerate LRM-5s or medium lasers we can compare to 6 average damage.  That gives 3 LAC-2s, 3 heatsinks, and 1 ton of ammo for a total of 16 tons compared to one LRM-10, 4 heatsinks, one SRM-4, and 3 tons of ammo (2 LRM 1 SRM) for a total of 14 tons.  This is still not favorable to the LAC-2s. 

Take a hypothetical 3025 variant someone suggested, the Clint 2-3T . . . swap that AC/5 for a LAC/2 and you have cut the weight of the gun down by 4t.  Which is a LOT you could add to that design . . . you could max the armor (52% sq), add a few heat sinks so it could jump and alpha w/ 1t for armor, you could replace the CT ML with a Large Laser if you wanted to, or quite a few other possibilities.  But now that fast low weight medium has a bit more to it while keeping a ranged plink'ing harasser.

Downgrading an AC-5 to a LAC-5 loses 60% of the damage to recover 44% of the weight.  This is a worse deal than losing 100% of the damage to recover 100% of the weight.  This frees up an additional 5 tons.  Your proposed LL swap could be a PPC swap with 2 more heatsinks to cover the difference for 4 of those tons and would reach out to AC-5 range with 800% more damage than the LAC-2.  There's no advantage to doing less damage.  Plinking is what you do when you can't do better. 

For a 3050 option . . . no longer does it really work on a light mech with the introduction of DHS, just too easy to put a ERLL like the Spider or a ERPPC like a Razorback.  To me it becomes a cheap ranged vehicle/speedster hunter . . . you can take a bog standard 3025 Scimitar, pull the AC/5 and put 2 LAC/5 with a single ton of ammo and get slightly more salvos- 11 if using precision.  Move about the battlefield and plink at the heavy/assault armor or damaged mechs for relatively low BV, precision just allows it to hunt its counterparts better.

You give up 20% of your long range damage for a 12.5% ammo increase (10% with precision due to unfavorable rounding) doing 10% less total damage (12% with precision) over the course of a sortie.  You also have to stay in the field longer to do that damage.  Bigger bins are not an advantage in this comparison.  For critting vehicles without a care for armor damage I'm pretty sure an LB-5X loaded with cluster is better.  The bonus is slightly lower than precision, but it rolls more hit locations and has better range bands. 

[Caedis Animus]

3 times bigger (3 in 36 instead of 1 in 36)...

Fun note: If you count pilot damage as equal to critical hits (which is a fair comparison IMHO) then AC ammo increases the number of criticals by ~62%.

The +1 TN penalty of AP ammo means you'll be causing more criticals firing standard ammo at TN 9 (67% more hits). If you're firing Precision ammo against a TMM+2 target TN6 (before either modifier) gets you better results!

Key in my statement is 'comfortable'. Never said I cared about the actual math behind it. And you aren't even close to the first person to tell me this, you're more like the twelfth.

The reason, as I stated in the very thing you just responded to, is because I feel more comfortable with two chances at a 12 than one at an 11 or 12. I prefer it on a purely personal level, and I don't care if this preference-one that I rarely have to worry about, considering how little I use either weapon system-leaves me somehow hamstrung. The chances of me actually playing in a game where this personal preference actually matters are slim to none.

[RevenVrake]

My main complaint about them is the dang name.

Light Auto-Cannon. When they had the great possibility of calling it the Snub-Nose Autocannon (They already have the Snub-Nose PPC) and then short handing it to the SNAC-2 and SNAC-5, making it snappy to say. It also invites the possibility of the SNAC-10 which could be interesting.

[Empyrus]

My main complaint about them is the dang name.

Light Auto-Cannon. When they had the great possibility of calling it the Snub-Nose Autocannon (They already have the Snub-Nose PPC) and then short handing it to the SNAC-2 and SNAC-5, making it snappy to say. It also invites the possibility of the SNAC-10 which could be interesting.

Damn it, now that you said this, it bothers me too.
I mean, fluff-wise they seem to be exactly that, ACs with barrels cut down, accounting for reduction in range and weight.

(And yes, the series should have been expanded to AC/10 and AC/20, with ML and MPL ranges respectively, perhaps.)

[UnLimiTeD]

Well, an LAC 20 is difficult.
The light ACs are always the range of the next larger regular version, and there isn't an AC >20.
A 10 would be great, though. Including the RAC version.
Still, we already know they get better with size. The LAC/2 is at the bottom no matter how you look at it.
It takes effort to be, on average, worse than an AC 5.

[mbear]

OK. Silly question time. Would a Light AC2 be useful on an aerospace fighter that was facing another fighter equipped with reflective armor (like the Simurgh Omnifighter)? The LAC/2 has a range advantage over SRMs, and wouldn't have its damage reduced by the armor. Maybe it would benefit by using precision ammo? (I don't know how precision ammo works in an aerospace context.)

(Yes, I'm really grasping at straws here to try to find a use for this weapon.)

[Scotty]

Aerospace units can't use alternate ammo types.

[Arkansas Warrior]

OK. Silly question time. Would a Light AC2 be useful on an aerospace fighter that was facing another fighter equipped with reflective armor (like the Simurgh Omnifighter)? The LAC/2 has a range advantage over SRMs, and wouldn't have its damage reduced by the armor. Maybe it would benefit by using precision ammo? (I don't know how precision ammo works in an aerospace context.)

(Yes, I'm really grasping at straws here to try to find a use for this weapon.)

An LRM-5 is better in just about every way for aerospace use.

[UnLimiTeD]

Both aren't particularly useful, however.
Seems to me that these days, nearly every ASF has 41+ armour on every facing, maybe excluding the aft on some lighter designs.
When it comes to the raw chance to hit at all against an ASF, from the ground, I think the LAC/2 might have a place as a Flak if the carrier just stands close to it's charges. Yes, an LBX would on average be better, but you get only one chance to hit. Of course, you're worse against everything else in return.

[Scotty]

Both aren't particularly useful, however.
Seems to me that these days, nearly every ASF has 41+ armour on every facing, maybe excluding the aft on some lighter designs.
When it comes to the raw chance to hit at all against an ASF, from the ground, I think the LAC/2 might have a place as a Flak if the carrier just stands close to it's charges. Yes, an LBX would on average be better, but you get only one chance to hit. Of course, you're worse against everything else in return.

An LB-2X is two tons more for an even better flak modifier and 50% more range.  Honestly, if you can't find the tonnage for an LB-2X, AA duty probably isn't for you.

[packhntr]

I'm in a campaign right now that has a couple of VTOLs with AC2's in them.....they're effective at harassment, but if they had LAC2s.....the would have been dead a long time ago.  The range is the only thing that keeps them alive.  LAC2s are just very heavy longer ranged machine guns. 

[The Eagle]

That makes me sad for the Poignard...though if memory serves there's an ERLL variant too.

[Caedis Animus]

An LB-2X is two tons more for an even better flak modifier and 50% more range.  Honestly, if you can't find the tonnage for an LB-2X, AA duty probably isn't for you.

Speaking of LB2Xs, I was checking around with the Gun to see if you could have a cheap-as-hell AA config for the Gun.

It works, but it's very mediocre. The ride lacks the pod space to mount an LB5X.

[Scotty]

It lacks the critical space to mount an LB-5X.  It's got plenty of pod space for one.  Important difference. :)

[Caedis Animus]

It lacks the critical space to mount an LB-5X.  It's got plenty of pod space for one.  Important difference. :)

I never understood the difference in terminology, as 'pod space' implies volume. That's why I always say 'pod space' when referring to critical slots on omnimechs.

[Scotty]

"Pod space" is universally used to refer to available tonnage for an Omni's base chassis in TROs.  The Timber Wolf has "37.5 tons of pod space available", for example.

[Caedis Animus]

I'm trying to find the nicest, least snarky way to say "Seriously, stop trying to help. I know what it's supposed to mean, and I knew pod space normally meant tonnage well before your attempts to correct me, so please cut it out and let's go back on topic."

I am not having much luck.

[mbear]

So about the Light AC/2...

The only place I can see it being used is with infantry as field guns on worlds that can't produce or import Rotary AC/2s. Although maybe, just maybe it would be a decent replacement for units mounting Rifles of various kinds (Arbiter, I'm looking at you).

[Colt Ward]

I can see two niches IMO- like I said before . . .

First, light or barely medium mechs like the 3025 Clint where you want to keep some ranged harassment, free up some tonnage to overall improve the design (armor on Clint) and you are wanting to say low heat so you do not add HS- use those free 10!  I also think it does not matter as much when we start talking about DHS being put on a machine- after all the IS ERLL is much more attractive for harassing if you turn those 10 free engine heat sinks into DHS.  This is why the Clint was my 3025 LAC retcon recommendation- and yes, I know the LAC/5 makes more sense for the model I mentioned but the 2 works pretty well in that slot.

Second, a vehicle hunter like I mentioned for the Scimitar . . . to go after vehicles its not the damage being thrown out, its the number of hits giving you chances at crits to make it a mission kill.  If that Hetzer gets ping'd by a fast hovertank before it can get in range with a result of either the AC/20 being knocked out or the vehicle immobilized, then it no longer matters.  So that 2 LAC/2 armed Scimitar is going to work better than a single AC/5- gives up 1 pt of damage for twice the opportunity for crits against vehicles.  Yes the LB-5X would be even better, but then its a judgement on availability.

As for AA . . . forget a LB- 2X or -5X on a GUN . . . the AFFS already has a suitable AA platform in the Garm.

[Atarlost]

I can see two niches IMO- like I said before . . .

First, light or barely medium mechs like the 3025 Clint where you want to keep some ranged harassment, free up some tonnage to overall improve the design (armor on Clint) and you are wanting to say low heat so you do not add HS- use those free 10!  I also think it does not matter as much when we start talking about DHS being put on a machine- after all the IS ERLL is much more attractive for harassing if you turn those 10 free engine heat sinks into DHS.  This is why the Clint was my 3025 LAC retcon recommendation- and yes, I know the LAC/5 makes more sense for the model I mentioned but the 2 works pretty well in that slot.

There's no advantage to not adding heatsinks, indeed there's a disadvantage: If you only have 10 SHS you cannot walk off the field after two engine crits.  If you have 11 you can.  If you have 12 you can run.  If you can produce enough heat to excuse enough heatsinks to start using crits you get crit padding.  Heatsinks, unlike ammo using weapons, only have good side effects.  Without advanced ammo you're better off losing the autocannon and its ammo bin entirely. 

Second, a vehicle hunter like I mentioned for the Scimitar . . . to go after vehicles its not the damage being thrown out, its the number of hits giving you chances at crits to make it a mission kill.  If that Hetzer gets ping'd by a fast hovertank before it can get in range with a result of either the AC/20 being knocked out or the vehicle immobilized, then it no longer matters.  So that 2 LAC/2 armed Scimitar is going to work better than a single AC/5- gives up 1 pt of damage for twice the opportunity for crits against vehicles.  Yes the LB-5X would be even better, but then its a judgement on availability.

The LACs are new.  The kerfluffle about the LFE proves that patent law exists in Battletech in this era.  LB-5X ACs have prior art in the Clan version and cannot be patented.  Until its patent protection expires the lower tech base of the LAC can't really come into play.  This is reflected in their availability ratings: XXED for the LB-5X and XXFC for the LACs.  The LB-10X is even more common at EFDC if you can swing it (on the Scimitar it requires removing the SRMs, but since it has no minimum range and does so much more damage that's hardly a sacrifice).  Even after the LAC patents have expired it's as easy to get LB-10X ACs as LAC-2s. 

Then there's the problem of ammo.  The thing that makes standard and light autocannons good on the modern battlefield is precision ammo, which is tech E same as the LBX autocannons and ammo.  If you can't make LBX ACs and ammo locally you also can't make precision ammo locally and if you can't make precision ammo locally you should be using the *canonical* version with the LRM-15.  You get slightly more hit locations (same median, but you're more likely to roll over 8 to get 3 than under 4 to get 1), more damage (even at a minimum cluster roll you get 5), and more advantageous range bands. 

[Colt Ward]

Love that you are ignoring the specific example- especially where I listed you could give it 1 or 2 more SHS (which maybe swallowed by the engine, I do not have HMP available right now), increase the armor and maybe give it another ML . . . to go with the 2 or 3 it already has . . . which means if it runs instead of jumping it has some flexibility.  You also see a LOT of the lights and low end mediums that only have the 10 engine heat sinks.  Before it was LRM5s FTW, now its Flashbulbs rule?  Either way gets boring and while I provided an answer to your earlier question, if you were looking for a Optimized reason you should have clearly said so before.

Scimitar is AC/5 & 2 SRM2s . . . what you are talking about is the Saracen.  The Saracen will also only have 8 shots per ton of ammo while the Scimitar will have 22.5 as described . . . I also specifically said a vehicle hunter with an example of going after something that struggles to get the +2 move mod.  Relying on a special ammo to make anything 'good' is a crutch.  A modified old 3025 Scimitar as a vehicle hunter gets more use out of a common chassis without resorting to rare/hard to get ammo . . . and Scorpions, Hetzers, LRM/SRM/MRM Carriers and some of the other 4/6 vehicles are going to be the most common designs you can find yourself facing, even if they do not get a lot of time on the table.  And your LRM is STILL one chance to hit . . . while I get 2 and no minimums for short range- which at 6 hexes or less gets me a 7 or 8 rather than trying to peg 7 hexes and only 7 to get the same LRMs SINGLE chance to hit.

Patents?  While that did come up with the LFE, its a joke considering the REST of BTU where the response is to send mechs with a cease & desist notice rather than lawyers.

[Scotty]

Love that you are ignoring the specific example- especially where I listed you could give it 1 or 2 more SHS (which maybe swallowed by the engine, I do not have HMP available right now)

This so colossally defeats the point of freeing up spare tonnage from a lighter weapon that I think it's an excellent point against LACs.

[Colt Ward]

It was one of the examples out of like 3 or 4 I provided about what could be done with that extra 4t from AC/5 to LAC/2 . . . my personal was to give it more armor to bring it up from 54%- 3t armor and a ML, which lets it run, fire everything and only overheat by 2 while the armor is at 87%.  If you look at the next sentence I point out a lot of those lighter designs do not go above the base 10 HS.  I also said that sort of reasoning does not work with DHS.

[Atarlost]

Love that you are ignoring the specific example- especially where I listed you could give it 1 or 2 more SHS (which maybe swallowed by the engine, I do not have HMP available right now), increase the armor and maybe give it another ML . . . to go with the 2 or 3 it already has . . . which means if it runs instead of jumping it has some flexibility.  You also see a LOT of the lights and low end mediums that only have the 10 engine heat sinks.  Before it was LRM5s FTW, now its Flashbulbs rule?  Either way gets boring and while I provided an answer to your earlier question, if you were looking for a Optimized reason you should have clearly said so before.

You can do more than twice as much with the other 5 tons you're wasting on a gun that's less than half the use of an AC-5 for more than half the weight.  If you get rid of it completely you can fit a PPC and two heatsinks and only build heat jumping if you respect the firing brackets, or 4t of armor and still fit a large laser, or install a LRM-10 or a LRM-5, 4t of armor, and another medium laser.  All of these are better than a similar build that keeps the LAC-2. 

Scimitar is AC/5 & 2 SRM2s . . . what you are talking about is the Saracen. 

Know your variants.
http://www.sarna.net/wiki/Scimitar#Variants
It's a thing.
http://masterunitlist.info/Unit/Details/2830/scimitar-medium-hover-tank-missile
It's not merely the product of wiki vandalism. 

Patents?  While that did come up with the LFE, its a joke considering the REST of BTU where the response is to send mechs with a cease & desist notice rather than lawyers.

Except in the era of sphere-wide peace and brotherhood and saving the mechs for fighting the Clans that is the Second Star League and the era of worrying about the Blakist common enemy.  Which are the eras in which the light autocannons exist and are rare.  The fact of the matter is that light autocannons have worse availability than more advanced autocannons until the dark ages.  No one is taking advantage of their simple construction to produce them all over the place for local use.  If they were they'd have a higher availability rating.  Either people are refusing to produce an easy to produce weapon system (including the LAC-5 which everyone agrees is actually good) for no reason whatsoever even when people are reviving Age of War junkers, or patents matter. 

[MightyBolamite]

So this has been bouncing around in my head for a couple of days. Would a LAC2 be worth it on a fast light using stealth? Now, I realize that a normal AC2 would be better, but still. Low heat with high range, I'm thinking with the special ammo it might be a reasonable harasser.

[Scotty]

So this has been bouncing around in my head for a couple of days. Would a LAC2 be worth it on a fast light using stealth? Now, I realize that a normal AC2 would be better, but still. Low heat with high range, I'm thinking with the special ammo it might be a reasonable harasser.

No.  You're better off with a Light PPC if you want damage at decent range, and you still won't even come close to capping out a bunch of DHSs.

[Caedis Animus]

No.  You're better off with a Light PPC if you want damage at decent range, and you still won't even come close to capping out a bunch of DHSs.

Hell, if you needed/wanted Anti-Infantry utility, swapping the LAC-2 for an LPPC in this case would even buy you two IS Machine Guns+whatever ammo you need. Assuming one of the 'specialty ammo' types Bolamite was talking about was fletchette.