Orphan Equipment ?

[Col Toda]

Places in Battletech  particularly in the periphery  ought to have developed  weapon and other systems to defend themselves  that would not exist anywhere else.  I not talking about something adopted by others like Rocket  Launchers  . Unique items not found anywhere else and not cost effective to adopt anywhere  else normally  seen only in an aspect in an RPG .

Examples : Rail Road Artillery  ( same stats as cruise missile 50 w 1 shot every 8 to ten minutes just used as opening shot followed by tank attacks 

AC/ 15 which 4/8/12 range brackets 6 shots per ton   
15 ton weapon  .

Medium  Gauss Rifle 12 damage same range brackets as ER PPC but a 3 minimum range 1 ton 12 shots 1 ton 1 crit less than normal  IS Gauss Rifle .

What have you seen ? What have you encountered? In  an isolated  one off out of the way corner in the Battletech  universe ?

[Maingunnery]

Custom weapons?

[RifleMech]

Places in Battletech  particularly in the periphery  ought to have developed  weapon and other systems to defend themselves  that would not exist anywhere else.  I not talking about something adopted by others like Rocket  Launchers  . Unique items not found anywhere else and not cost effective to adopt anywhere  else normally  seen only in an aspect in an RPG .

(snip)

I agree that there's going to be weapons see on one planet and not seen on another. The universe is too big for there not to be non-standard weaponry. I think some would be prototypes, functional but not production worthy. Some do go into production but don't match the stats some how. They can be better quality, or worse, or just different for whatever reason.


I've used quirks to make weapons different from standard.

I've used odd stats for weapons to represent non standard versions.

I've used odd weapons like the AC/15, and Medium Gauss Rifle.

I've also tried to come up with rules for weapon's fluff that don't match the rules. Like lasers with variable damage settings and partially reflective armor.  I've also worked on different ACs like Gatling and Gast Guns to match fluff.

I still use some weapons and equipment that has been dropped from the rules.

I've tried to come up with different weapons classes like Masers and Railguns but I'm still working on them.

I love using tech from XTRO:1945, Third League, and Nebula California. (I'm still trying to figure out some of the Third League Tech though. :(

I figured out some rules for "modern" myomer catapults.

I've allowed Infantry to use Missile and Mortar weapons the same way Cannons can be used for field guns and field artillery. Nebelwerfers!  >:D

[Cannonshop]

I agree that there's going to be weapons see on one planet and not seen on another. The universe is too big for there not to be non-standard weaponry. I think some would be prototypes, functional but not production worthy. Some do go into production but don't match the stats some how. They can be better quality, or worse, or just different for whatever reason.


I've used quirks to make weapons different from standard.

I've used odd stats for weapons to represent non standard versions.

I've used odd weapons like the AC/15, and Medium Gauss Rifle.

I've also tried to come up with rules for weapon's fluff that don't match the rules. Like lasers with variable damage settings and partially reflective armor.  I've also worked on different ACs like Gatling and Gast Guns to match fluff.

I still use some weapons and equipment that has been dropped from the rules.

I've tried to come up with different weapons classes like Masers and Railguns but I'm still working on them.

I love using tech from XTRO:1945, Third League, and Nebula California. (I'm still trying to figure out some of the Third League Tech though. :(

I figured out some rules for "modern" myomer catapults.

I've allowed Infantry to use Missile and Mortar weapons the same way Cannons can be used for field guns and field artillery. Nebelwerfers!  >:D

Thing I see, is that we really don't have the equivalent of a "Fire fusion and steel" for Battletech.  Also, that one of the major unwritten rules is that the Clanners will do anything your faction can think of, only it will be better, stronger, more powerful, lighter, and this applies even if it's something they would never logically do on their own.  (This appears to be the only FIRM rule about Battletech weapons development-that no matter what, even if it's completely against their culture as written, the clanners will do it better than you do.)

That said, we're really discussing custom weapons and/or equipment, and I've got a few...

AC/15; Shots/ton 7, Range brackets: 4/8/12, heat 5, ballistic, 13 tons  ammo explosion does 15/remaining shot

Alternate heavy Machine gun:  Shots/ton: 100 (50 for half-ton lots) 2/4/6, heat 0, weight: .75 tons, damage 2, ammo explosion does 3 points per remaining shot. (this system was designed by a periphery state not run by idiots willing to waste a ton on something that is outranged by pistols) damage vs. infantry: 2D6

Non-battlesuit sensor dispenser: compatible with vehicles, battlearmor and 'mechs, the dispenser contains 4 drop-deployable sensor probes (.05 tons or 5KG per) and is derived from the 3026 version of the Warrior H-7.  Sensors are deployed in the movement phase and cover a radius of 1.5 hexes (aka take your artillery splash diagram.  one hex in the center, and six hexes in a circle around it)  this reveals hidden units within the radius of detection, and gives a -1 to the targeting numbers for indirect artillery fire or indirect (but not direct) LRM fire within the radius of effect.  (Neutralized by ECM) total tonnage: .25 per dispenser unit.  Overlapping coverage does not stack bonuses.

[RifleMech]

Thing I see, is that we really don't have the equivalent of a "Fire fusion and steel" for Battletech.  Also, that one of the major unwritten rules is that the Clanners will do anything your faction can think of, only it will be better, stronger, more powerful, lighter, and this applies even if it's something they would never logically do on their own.  (This appears to be the only FIRM rule about Battletech weapons development-that no matter what, even if it's completely against their culture as written, the clanners will do it better than you do.)

There's a couple exceptions. Clan Rotary ACs do have better range but their weight looks the same and the Clan versions are bulkier. I'm also guessing that the Chemical Lasers are just made off of old plans or they should be lighter.

That said, we're really discussing custom weapons and/or equipment, and I've got a few...

AC/15; Shots/ton 7, Range brackets: 4/8/12, heat 5, ballistic, 13 tons  ammo explosion does 15/remaining shot

Alternate heavy Machine gun:  Shots/ton: 100 (50 for half-ton lots) 2/4/6, heat 0, weight: .75 tons, damage 2, ammo explosion does 3 points per remaining shot. (this system was designed by a periphery state not run by idiots willing to waste a ton on something that is outranged by pistols) damage vs. infantry: 2D6

Sounds good to me. I've used an AC/3 7 tons, 1 heat, 3 damage, 4/7/15/22 (Long) 33 rounds per ton and 2 crits.

Non-battlesuit sensor dispenser: compatible with vehicles, battlearmor and 'mechs, the dispenser contains 4 drop-deployable sensor probes (.05 tons or 5KG per) and is derived from the 3026 version of the Warrior H-7.  Sensors are deployed in the movement phase and cover a radius of 1.5 hexes (aka take your artillery splash diagram.  one hex in the center, and six hexes in a circle around it)  this reveals hidden units within the radius of detection, and gives a -1 to the targeting numbers for indirect artillery fire or indirect (but not direct) LRM fire within the radius of effect.  (Neutralized by ECM) total tonnage: .25 per dispenser unit.  Overlapping coverage does not stack bonuses.

I just used half the payload of the .5 ton Remote Sensor Dispenser.

[Intermittent_Coherence]

And here what I had in mind was hi tech ballista using myomer bundles.

[Mendrugo]

For truly non-standard gear, check out Far Country.

Steam-powered tanks with lacquered wooden armor using pneumatic rams to launch boulders out of barrels the diameter of industrial trash cans at other "hero" tanks, with infantry support mostly to keep the "hero" units from being swarmed and boarded.

[Retry]

I'm confused.  What's this thread for?  Home-brew equipment?

[Cannonshop]

I'm confused.  What's this thread for?  Home-brew equipment?

It pretty much HAS to be-anything with Canon stats is going to be 'not orphan' equipment.  I think the core here, is it needs to fill a percieved gap, either in the fluff, or a logical gap (like the AC/15 proposals) as being something that 'should' exist, but obviously does not, the premise being that in a universe with so many people spread out the way they are, not everyone has access to/reliance on the two basic STC's (Clan or Inner Sphere standardized equipment).

for example, my entry-the Warrior H-7 was fluffed in TRO 3026 (and 3026 revised) with a quarter-ton 'sensor dispenser' that was never statted.

The AC/15 is a logical gap item that people commented on for a long time, between the AC/10 and AC/20.

My version of the HMG is born of frustration with what the devs actually DID-making everyone copy off each other (Badly) instead of thinking for themselves.  (aka "Put more powder behind the same projectiles at the same rate of fire." instead of "bigger, slower bullets.")  basically trading mass for range instead of mass and range for damage.  (being honest here, there is literally no situation where the Inner Sphere HMG is better than just carrying two standard MGs.  None.  you're paying 1.5 times the mass of a medium laser for something that does small laser damage at less than small laser distances with poorer to-hit numbers. nobody would put that into production if they were born with both brain, and central nervous system.)

[RifleMech]

And here what I had in mind was hi tech ballista using myomer bundles.

Sounds good to me. :thumbsup: Human or Mech scale? or both?  >:D

For truly non-standard gear, check out Far Country.

Steam-powered tanks with lacquered wooden armor using pneumatic rams to launch boulders out of barrels the diameter of industrial trash cans at other "hero" tanks, with infantry support mostly to keep the "hero" units from being swarmed and boarded.

I remembered the steam powered tanks. Using pneumatic rams to fire the boulders I didn't.  I'll have to go reread it.  :thumbsup:

It pretty much HAS to be-anything with Canon stats is going to be 'not orphan' equipment.  I think the core here, is it needs to fill a percieved gap, either in the fluff, or a logical gap (like the AC/15 proposals) as being something that 'should' exist, but obviously does not, the premise being that in a universe with so many people spread out the way they are, not everyone has access to/reliance on the two basic STC's (Clan or Inner Sphere standardized equipment).

for example, my entry-the Warrior H-7 was fluffed in TRO 3026 (and 3026 revised) with a quarter-ton 'sensor dispenser' that was never statted.

We did get stats for a Remote Sensor Dispenser but it's a half ton. I think TPTB didn't want to mess with more quarter tonnage equipment. I just reduce the payload by half. Same for when using older versions.

I'm still working on rules for sensors. There should be something before Beagles were introduced but I don't want them to be better then EW Equipment. I think I've got it though. The equipment for the Long Tom is a bit tougher.

The AC/15 is a logical gap item that people commented on for a long time, between the AC/10 and AC/20.

My version of the HMG is born of frustration with what the devs actually DID-making everyone copy off each other (Badly) instead of thinking for themselves.  (aka "Put more powder behind the same projectiles at the same rate of fire." instead of "bigger, slower bullets.")  basically trading mass for range instead of mass and range for damage.  (being honest here, there is literally no situation where the Inner Sphere HMG is better than just carrying two standard MGs.  None.  you're paying 1.5 times the mass of a medium laser for something that does small laser damage at less than small laser distances with poorer to-hit numbers. nobody would put that into production if they were born with both brain, and central nervous system.)

Yeah the HMG doesn't look that good. Plus the way MGs are it makes me think that they can't be Pre-Spaceflight. They do the same thing ACs do. The bigger they are the shorter the range. Smaller increased range.

[Cannonshop]

Sounds good to me. :thumbsup: Human or Mech scale? or both?  >:D


I remembered the steam powered tanks. Using pneumatic rams to fire the boulders I didn't.  I'll have to go reread it.  :thumbsup:


We did get stats for a Remote Sensor Dispenser but it's a half ton. I think TPTB didn't want to mess with more quarter tonnage equipment. I just reduce the payload by half. Same for when using older versions.

I'm still working on rules for sensors. There should be something before Beagles were introduced but I don't want them to be better then EW Equipment. I think I've got it though. The equipment for the Long Tom is a bit tougher.


Yeah the HMG doesn't look that good. Plus the way MGs are it makes me think that they can't be Pre-Spaceflight. They do the same thing ACs do. The bigger they are the shorter the range. Smaller increased range.

I actually have a different theory; They can be.  here's how:

imagine a standardized ammunition feed set up to handle 12.7mm (.50 caliber BMG).  to make a "Heavy" machine-gun, in battletech terms, you take the bottleneck case, and make it straight walled like a 37mm Maxim "Pom Pom" cartridge, then insert your favorite explosive filler with a base-fused detonator and HESH tip.  what this does: radically shortens your effective range (since you're lobbing a significantly heavier projectile with the same, or even a reduced, powder load).  for the "Light" you trade out the tungsten-steel core from the bullet for aluminium with tetrahedral carbon in the tip.  result: radical increase in range, radical decrease in striking power.

Hence, "Heavy" and "Light" machineguns as we see with the canon.  Maybe alter the weapon further, a faster burning powder or something, or slight difference in dimensions to prevent loading one into the other, but the bigger bore would require a heavier barrel and mechanism, while the 'lighter' weapon is essentially indistinguishable in terms of mass because...reasons?

Okay, now, MY version...

Hotter round, bigger propellant load (more damage from ammo explosions, obviously) same projectile, slightly heavier barrels to absorb the increased pressure, rather than needing to be heavier due to being flat-ass bigger.  the hotter round will also require ACTUAL buttressing of the breech and firing mechanisms, so you gain a bit of weight there too, but it's more like matching a magnum round vs. an intermediate;  MY version gains range for the extra weight instead of damage, but keeps the same cyclic rate as the standard machine-guns everyone else is using.  end result being the same damage, increased range, nastier ammo explosion, but it actually makes sense that someone would build it.

Unlike the IS HMG, which makes zero sense for anyone to invest the metal to manufacture unless they're astonishingly stupid.

the other thing it does, is it's not copying Clan Equipment badly. It reflects someone actually doing their own homework once in a while or making decisions other than "let's emulate shit we can't build that don't fit any of our needs."


Moving along with that...

Alternate Rifle Cannon Munitions.

yes, you heard me right.  The Rifle cannon can't use Autocannon specialty rounds, why wouldn't someone who's still making them (or has started making them) come up with their own?? doesn't make sense, does it?

Beehive:  Beehive muntions do the following: 
(a) Light Rifle Beehive: 1D6 vs. Infantry (unarmored) out to effective range in the hex of the targeted unit, and leaves a 1d3 (1D6/2) minefield that only effects infantry behind (cleared on detonation)
(b) Medium Rifle: 2D6 vs. Infantry, leaves 1D6 explosive munitions behind (only affects infantry units).
(c) Heavy Rifle : 3D6 vs. Infantry, leaves 1D6 plus 2 point minefield.

Breaching/Clearing shot  inflicts damage directly to woods, light buildings and other clearable cover.  inflicts half damage on infantry and other combat units.

Indirect Support rounds  Inflicts 1/3 (Round Up) rated damage to target hex, may be fired indirect at hexes using LRM indirect fire rules and a spotter, or direct-fired at a hex.

Anti-armor dual stage penetrator  Full damage to BAR 9 armor, -1 damage to BAR 10, +2 Penalty to-hit, half sized ammo bin, double damage ammunition explosion.

[RifleMech]

I actually have a different theory; They can be.  here's how:

imagine a standardized ammunition feed set up to handle 12.7mm (.50 caliber BMG).  to make a "Heavy" machine-gun, in battletech terms, you take the bottleneck case, and make it straight walled like a 37mm Maxim "Pom Pom" cartridge, then insert your favorite explosive filler with a base-fused detonator and HESH tip.  what this does: radically shortens your effective range (since you're lobbing a significantly heavier projectile with the same, or even a reduced, powder load).  for the "Light" you trade out the tungsten-steel core from the bullet for aluminium with tetrahedral carbon in the tip.  result: radical increase in range, radical decrease in striking power.

Hence, "Heavy" and "Light" machineguns as we see with the canon.  Maybe alter the weapon further, a faster burning powder or something, or slight difference in dimensions to prevent loading one into the other, but the bigger bore would require a heavier barrel and mechanism, while the 'lighter' weapon is essentially indistinguishable in terms of mass because...reasons?

Okay, now, MY version...

Hotter round, bigger propellant load (more damage from ammo explosions, obviously) same projectile, slightly heavier barrels to absorb the increased pressure, rather than needing to be heavier due to being flat-ass bigger.  the hotter round will also require ACTUAL buttressing of the breech and firing mechanisms, so you gain a bit of weight there too, but it's more like matching a magnum round vs. an intermediate;  MY version gains range for the extra weight instead of damage, but keeps the same cyclic rate as the standard machine-guns everyone else is using.  end result being the same damage, increased range, nastier ammo explosion, but it actually makes sense that someone would build it.

Unlike the IS HMG, which makes zero sense for anyone to invest the metal to manufacture unless they're astonishingly stupid.

the other thing it does, is it's not copying Clan Equipment badly. It reflects someone actually doing their own homework once in a while or making decisions other than "let's emulate shit we can't build that don't fit any of our needs."

Problem is MGs are fluffed as being 20mm-30mm. And they still function like small autocannons. The bigger they get the shorter the range.

My head canon has the AC rounds not only getting bigger but having the propellant reduced, thus the reduced range. In my head this is in part because only so much recoil can be absorbed. And a 150+mm cannon firing 1 round a second would generate a lot of recoil. It's why even the UACs which are made to fire faster break. Or at least that's how it is in my head.

Moving along with that...

Alternate Rifle Cannon Munitions.

yes, you heard me right.  The Rifle cannon can't use Autocannon specialty rounds, why wouldn't someone who's still making them (or has started making them) come up with their own?? doesn't make sense, does it?

Beehive:  Beehive muntions do the following: 
(a) Light Rifle Beehive: 1D6 vs. Infantry (unarmored) out to effective range in the hex of the targeted unit, and leaves a 1d3 (1D6/2) minefield that only effects infantry behind (cleared on detonation)
(b) Medium Rifle: 2D6 vs. Infantry, leaves 1D6 explosive munitions behind (only affects infantry units).
(c) Heavy Rifle : 3D6 vs. Infantry, leaves 1D6 plus 2 point minefield.

Breaching/Clearing shot  inflicts damage directly to woods, light buildings and other clearable cover.  inflicts half damage on infantry and other combat units.

Indirect Support rounds  Inflicts 1/3 (Round Up) rated damage to target hex, may be fired indirect at hexes using LRM indirect fire rules and a spotter, or direct-fired at a hex.

Anti-armor dual stage penetrator  Full damage to BAR 9 armor, -1 damage to BAR 10, +2 Penalty to-hit, half sized ammo bin, double damage ammunition explosion.

I like the ammo types but I don't know why RCs couldn't use AC rounds. In my head I flip it. The Autocannon rounds are based on Rifle Cannon rounds. I also think RC should be able to fire indirectly. I think there could be smoke, incendiary, and air burst rounds too.

[Maingunnery]

Rocket ammo (Deadhead) for LRMs & SRMs.

[Cannonshop]

Problem is MGs are fluffed as being 20mm-30mm. And they still function like small autocannons. The bigger they get the shorter the range.

My head canon has the AC rounds not only getting bigger but having the propellant reduced, thus the reduced range. In my head this is in part because only so much recoil can be absorbed. And a 150+mm cannon firing 1 round a second would generate a lot of recoil. It's why even the UACs which are made to fire faster break. Or at least that's how it is in my head.



I like the ammo types but I don't know why RCs couldn't use AC rounds. In my head I flip it. The Autocannon rounds are based on Rifle Cannon rounds. I also think RC should be able to fire indirectly. I think there could be smoke, incendiary, and air burst rounds too.

Fluff on MG's in the TROs run everything from 12.7 to 30mm-and that's just the standard ones.  As I said in my initial comment, we don't have a "Fire, Fusion, and Steel" type publication for Battletech.  (This becomes REALLY apparent when you look at the overlaps; the Crusher autocannon 20 in the nose of a 'mechbuster is 20mm (TRO 3026), the Cauldron-Born's ultra-20 is 208mm.) Yet somehow the ammunition for one, fits in the other.

I could actually see Rifle Cannons having a whole selection of their own specialty munitions that aren't necessarily 'so' with autocannons, (there are a lot of ways to use a device for throwing a given weight a given distance ballistically) without crossing the rule of "it can't be as good against armor as an autocannon".

Including a WP/Smoke (Incendiary smoke) load, "marker" load, and various 'very light artillery' loads. (but none of those would likely be canonized.)

[Daryk]

In my head canon, the vanilla MG is a GAU-19 (tri-barrel, .50 cal machine gun), while the heavy is the 6-barrel version (twice the fire rate).  Stats here.

[Cannonshop]

In my head canon, the vanilla MG is a GAU-19 (tri-barrel, .50 cal machine gun), while the heavy is the 6-barrel version (twice the fire rate).  Stats here.

in order to get the effective 30% drop in range you still need to alter one (or more) of the following:

Projectile weight/mass
Propellant charge
Barrel length.

why? because  effective ranges are largely governed by projectile velocity, while damage can be either kinetic impact or explosive payload.

seen in practice, adding the other three barrels adds mass, but doesn't degrade your projectile range or increase  your spread (degrading accuracy).

BUT... we see effective range drops between the types (Light, standard, and Heavy machine guns).  this suggests differences in propellant vs. payload between the types.

This, in turn, raises a pretty basic question: what's your limiting factor-because it isn't material strength in the breech (Unless you're using cast bronze).

The most obvious one, is something you see in the AR-15 community-that being a set of dimensions you can't exceed on an AR-15 lower reciever.  (Hence why .50 Beowulf is basically a hot magnum pistol round with a low velocity).

if everyone in the 'big two' are confined tot he same length/width sizes, (say, a 37mmx120mm diameter cylinder) because that's what all the standardized ammunition feeds for "Machine gun" is on their STC, to get more damage, you need a bigger projectile, which means a smaller propellant charge (HMG), while to get longer ranges, you'd reduce the mass/facing surface area of your projectile and add propellant (LMG).  This fits the ballistic profiles we see.

It also suggests virtually everyone as settled  on a logistical standard established sometime in the past, without questioning it or its usefulness.

(This too, has happened before with the fall of the Western Roman empire.  The reason for the standard railroad gage comes from cart tracks left in old roman roads across europe centuries before the first steam locomotive.)

Of course, this in turn leaves the possibility that someone might elect to do something different-either because they're able to question the handed-down wisdom, or because they have a need, and don't have the education telling them something is impossible, impractical, or wrong because it isn't relying on what everyone else has been doing for the last thousand years.

alternatively, they might be willing to design their OWN feed mechanisms instead of just changing out a barrel and a chamber and calling it a day.

[Daryk]

I was simply relying on twice the fire rate to deliver something less than twice the number of effective hits, and the recoil to reduce the accuracy.

[Cannonshop]

I was simply relying on twice the fire rate to deliver something less than twice the number of effective hits, and the recoil to reduce the accuracy.

Your recoil would have to be significantly higher to degrade accuracy by that much, esp. in a stabilized mount (which you'd have on any remote weapon mounting like a 'mech)-it would have to overcome the stabilization AND the mass of the vehicle it's mounted on.

doesn't seem likely on something that tops out at 37mm with an effective range of less than 2000 yards unless your 'mech is made of gelatin.

(this is one of the big logical problems-the "physical limits" don't make as much sense as "cultural inertia".)

[Daryk]

Oh sure... if the canon HMG wasn't so... odd... my head canon would make more sense.

[Cannonshop]

Oh sure... if the canon HMG wasn't so... odd... my head canon would make more sense.

One thing to do when designing this stuff, is to accept that "x exists for a reasonable reason."

Cultural inertia is ACTUALLY a reasonable reason.   back in the Terran Alliance days, all your colonies shipped with a copy of the same technical library.  The reasons for the standards in that library were lost to time (because that happens) so everyone is using the same set of engineering standards without questioning why, or if there are parts left out, or if some/most/all of it was influenced by a few existing mega-corporations on old Earth who don't want to deal with competitors.

ends up being a bit like the railroad gauge thing in Europe and eventually North America.  Everyone does it because everyone is doing it.

the databases taken by Kerensky were compiled from the same information sources, likely with the same gaps in information.

hence, everyone is using the standard ammunition feed dimension for a given weapons class (autocannon, missile, or machine gun) because t hat's what everyone is using.

a tautology, if you will.  Note that in 300 years of frantic development, the Clans were unable to beat the jamming problem on ultra autocannons, but that with less than 30 years of effort, the Federated Suns figured out how to make one that can be unjammed in the field without going back to a repair bay.

how is this possible?  consider that the Federated Suns has a high rate of illiteracy and a poorly funded education system (per the canon).  the only explanation that makes sense is that the NAIS engineers didn't know they couldn't beat the problem-so they did.

large entities (corporations, governments and the like) tend to have a LOT of cultural inertia-that is, they tend to have difficulty enacting or coping with change.  The more centralized your organization, the more pronounced that tendency becomes.  They are fine at 'evolving' existing designs (turning the M-1 Garand into the M-14, for example), but not so good at coming up with NEW things, or approaching problems with a clean sheet.

aka they're good at "This is how this is done" without asking "Why are we doing it this way?" They're even worse at "Let's do something differently".

[Col Toda]

The point of this thread is weird out of the way places having to develop and make  weapons themselves  . The weapons produced are non standard  and not as nice or standardized as the listed ones . That may very well get abandoned when sufficient contact and trade occurs . For one reason or another it would not normally leave the place of origin  .  The weapons and systems  I  used the term Orphan  to express unsupported and alone .  The AC 15 was deliberately  heavier and shot per ton lower  on purpose  as not to give an incentive  to profligate.

[RifleMech]

Rocket ammo (Deadhead) for LRMs & SRMs.

Aren't Deadfire Missiles still a thing?

I'd like something like the MGM-51 Shillelagh for ACs and RCs.

Fluff on MG's in the TROs run everything from 12.7 to 30mm-and that's just the standard ones.  As I said in my initial comment, we don't have a "Fire, Fusion, and Steel" type publication for Battletech.  (This becomes REALLY apparent when you look at the overlaps; the Crusher autocannon 20 in the nose of a 'mechbuster is 20mm (TRO 3026), the Cauldron-Born's ultra-20 is 208mm.) Yet somehow the ammunition for one, fits in the other.

Where is the fluff for 12.7mm Machine Guns? I also looked at TRO:3026 for the Mechbuster Fighter. It says it has a Zeus 75 Mark IX Autocannon, Type 20 that fires 4 round bursts of hyper-velocity depleted uranium armor penetrators  (HDUAP). I don't see anything about size in mm.

I do agree that it's odd that weapons from one can work in another. I think it's done for came simplicity. There are time where ammo sharing isn't allowed when campaigning. It's a pain but adds some realism.

I could actually see Rifle Cannons having a whole selection of their own specialty munitions that aren't necessarily 'so' with autocannons, (there are a lot of ways to use a device for throwing a given weight a given distance ballistically) without crossing the rule of "it can't be as good against armor as an autocannon".

Including a WP/Smoke (Incendiary smoke) load, "marker" load, and various 'very light artillery' loads. (but none of those would likely be canonized.)

Probably not but that doesn't mean we can't try to get some alternate ammo loads approved. The rest we use in our games :)

[Col Toda]

Yes deadfire LRMs is still a thing . Knew a player that loaded a ton of it . He was an elite gunner with missles and it had a shorter range and minimum range . Paired well with standard large lasers .

[RifleMech]

Cool.  I suppose they would work better with an elite gunner.