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Musings on the humble ACR

nobby-w

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What might the ACR market look like after a few centuries or millenia?

The humble ACR is the AK of the Traveller universe, forming the staple of many a mercenary campaign. Although considered obsolescent it is arguably the most widely used small arm in most Traveller settings. Most Traveller rule system variants make it reasonably effective against all but the heaviest body armour.

I dare say some folks in this forum have implemented similar ideas in their 'verses, and I have certainly been using most of these since the 1980s. However, here's an article that pulls it together in one place and pontificates a little on the wider ecosystem of the ACR.

A common design like this inspires variants and an ecosystem of components and third-party manufacturers. Similar phenomena can be seen with AK designs (many third party factories during the cold war) and the ecosystem of AR pattern rifles and parts on today's market. Here are some thoughts on what this sort of market might look like in a Traveller 'verse.

Major ACR Variants
Here is a starter for some major ACR variants that might have sufficiently unique characteristics to be noteworthy.
  • Standard battle rifle: This is the ACR as described in Mercenary and various other rule sets. It is described in depth elsewhere, but we'll note its key features as: Electronic sight, Gyro unit and RAM grenade launcher.
  • Personal defence weapon: A cut down version for self-defence by rear-echelon troops, or possibly used for built-up locations or other confined areas. This would be 10-15cm shorter than a standard ACR, perhaps 0.5kg lighter at 3kg and would miss most of the key features listed above. It is fitted with simple iron sights or maybe an optical or parallax sight and is somewhat cheaper at around Cr400.
  • Counter-sniper variant: This is a variant of the ACR with a heavier barrel, designed to issue to designated marksmen or similar specialists. Although not a true sniping weapon, this has a longer effective range than a standard ACR. It is fitted with a match barrel, a bipod, an uprated sight and a gyro unit, but no grenade launcher. At Cr2,000 this variant is more expensive than a standard ACR due to the higher spec barrel, sight and quality control. It is also somewhat heavier at 4.5kg.
  • Light Support Weapon: A heavy barrel variant designed to provide section level fire support. It can take a larger magazine (which could also be fitted to a standard ACR) and the barrel has an up-rated heat sink to facilitate higher rates of fire. This variant has a bipod, a sight similar to that on the standard ACR but no grenade launcher.

Other weapons firing the same ammunition
The ubiquitious nature of the ACR makes ammunition relatively cheap, both due to economies of scale in manufacture and presence of surplus ammunition on the secondary market. A variety of other weapons are introduced - both military and civilian - to make use of the commonality of ammunition with the ACR.
  • 'Advanced' Machine Gun (AMG): A general purpose machine gun firing the same ammunition as an ACR. This could be mounted on a vehicle or carried by infantry. It is fed from a belt of ammunition held in a box that can be attached to the side of the weapon; some variants can take two belts, or a belt and a secondary magazine feed. It has a bipod, a sight similar to that on the ACR and a much heavier barrel with a heat sink arrangement for heat dissipation. The heavy barrel and heatsink make this weapon much heaver than a standard ACR at approximately 8kg with a unit cost around Cr5,000
  • 9mm Rotary Gun: A gatling style rotary gun with a high rate of fire. This can be mounted on grav sleds or other vehicles, typically in pintel mounts such as door guns. Ammunition is fed from drums holding approximately 1,000 rounds (some may be larger). Even on an unstabilised pintel mount, the rate of fire makes them quite effective against ground targets. Rotary guns of this type can be mounted on a tripod but the consumption of ammunition makes them somewhat impractical as infantry weapons. The base weapon weighs approximately 15kg with a unit cost around Cr10,000.
  • 9mm Rifle: A civilian hunting rifle built to fire the same ammunition as the ACR, taking advantage of wide availability and low cost. The relatively powerful 9mm rounds make this weapon a popular hunting rifle against medium-sized animals up to 2,000kg. Some variants of this are purpose built hunting rifles and some are little more than commercial variants of the ACR modified to comply with local regulations. Usually these rifles will lack the electronic sights, gyro units and grenade launcher, substantially reducing the price to approximately Cr350; normally the rifle will weigh around 3kg. Normally civilian variants of the rifle use a smaller 5 or 10 round magazine, although many will fit standard ACR magazines as well.
  • Sniping or match Rifles: Although lasers tend to be popular in sniping roles, sniper rifles firing ACR ammunition do get issued in quantity. These tend to be purpose-built weapons rather than accuratised versions of the ACR. Normally they are fitted with a bipod, high-specification sight and a heavy match barrel. Some may take smaller magazines but (like civilian rifles) many will accept standard ACR magazines. The heavy barrel and high-specification sight mean this type of weapon typically weighs approximately 6kg with a typical unit cost of Cr5,000

High-tech life extension programmes
Although it has reasonable penetration, the discarding sabot ammunition used by the ACR is designed primarily for high volume manufacture, sacrificing some performance in order to make it cheap enough to issue as a standard service round to infantry. Higher-tech body armour makes these rounds less effective from TL11-12, giving the ACR its reputation for obsolescence.

At TL12, stable superdense armour technology also informs superdense penetrators for armour piercing rounds, and TL12 superdense armour-piercing rounds are often used to extend the service life of existing ACRs. These are substantially more expensive than standard DS rounds but have higher penetration, making the ACR effective enough against this type of armour to remain useful.

This type of armour piercing round might be expected to have a unit cost an order of magnitude more than standard D/S ammunition. It is also less of a mass-market item than standard D/S rounds so is likely to be less widely available to riffraff like your party. However, a well connected dealer may be able to lay their hands on a few cases from time to time ...

Third party modifications and accessories
One might also expect to see a variety of third-party modifications and accessories such as uprated sights, attachments for torches or laser spot projectors or even bottle openers.

Where might one encounter these?
(Or, how are a bunch of riffraff like your party going to get hold of them)
  • Most of these would be germane to a mercenary campaign, although one could reasonably encounter some of these items in a more general adventuring setting.
  • The 9mm rifle (or a match grade variant) might be a popular civilian sporting weapon due to availability of relatively cheap surplus ammunition. With appropriate permits it might be imported into many jurisdictions without looking out of the ordinary.1 It just happens to be capable of firing armour-piercing ammo ...
  • ACR or PDW variants might be found in a ship's locker, in the hands of NPCs, or purchased through not-so-legal channels by a streetwise party. ACRs are widely available on the grey market so all sorts of shadier folks might be encountered using them. PDW variants are shorter and handier and may be more popular with criminal elements such as gangs. Depending on local law level and what's being secured one might also encounter police or security guards carrying ACRs. ACRs are going to be the most widely used service rifle in most regions of a Traveller 'verse so they're a sort of de-facto standard for arming folks who might have cause to defend themselves as a part of their job.
  • Support weapons might be issued to troop units in a mercenary setting. Rotary guns might be fitted to a grav sled, perhaps as door gun mounts.
Because of their ubiquitous nature they are also likely to be imported to worlds with lower tech levels. Poorer worlds might not be able to afford ACRs and may drop back to rifles or assault rifles, but the ubiquitous nature of the ACR means it will show up in all sorts of places.

1For example, one could make a roll on 2D for 8+ with a DM of -1 per law level over 5. Positive DMs might be allowed for skills such as Admin or Hunting.

I've got some stats for these in various CT/MT era combat systems. BBCode table syntax is quite fiddly but I can write up what I've used if folks are interested.
 
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Just for fun, I created an ACR in T5's Gunmaker. Didn't see an option to add the grenade launcher, but otherwise this is what comes out:

ACR-10
Wx: R=3 Cr1,500 2.88kg E=-3 B=-3 Bullet-4 Frag-2
 
I look at the gyro for ACR and Gauss as a necessary corrective to the higher kick these rounds will produce.

The CT/Striker 7mm carbine with slug ammunition would seem to me to be the civilian version. It has virtually the same characteristics as the 7mm autorifle, but is lighter and cheaper. Of course, with DS it is longer ranged and more potent.
 
The CT/Striker 7mm carbine with slug ammunition would seem to me to be the civilian version.
You could easily have civilian hunting rifles in either calibre. The 9mm rifle isn't a civilian version of the ACR1, it's a commercial hunting rifle that uses ammunition that's cheap because it's manufactured in large quantity due to its use in military applications. This is the same process that drove the popularity of calibres such as .308, .223 or 7.62x39 (or previous generations such as .303 or .30-06). Rifles in these calibres are popular because of the availability of cheap ammunition, and in some cases availability of surplus rifles such as happened after the end of WWI and WWII.

1 Although some variants could be based on ACRs modified to comply with local legislation (q.v. Saigas).
 
What about the Pistol equivalent?

Not much room for it in Striker between the slug pistol bookends of the 9mm magnum revolver and the Gauss pistol, plus the snub and the laser.

Guess I would tend to assign it a value the other pistols don't have, more of a submachine pistol burst, go for small package high probability hit rather then penetration with the other high tech pistols.

MgT1E Central Supply Catalog has a wealth of AC-family weapons if you want to look at other takes.
 
Not much room for it in Striker between the slug pistol bookends of the 9mm magnum revolver and the Gauss pistol, plus the snub and the laser.

Now that is a odd jump.

I would go from Auto Pistol to Advanced Combat Pistol, with both having their related magnums....

Though to be honest it probably would come out looking like a High velocity Snub pistol.
 
I believe T4 described "gauss augmented" ACR weaponry. Where the initial propelling energy came from a chemical reaction, but that the barrel also helped pull the projectile along to give it more penetration.

I've not seen MgT equipment guide, but cross pollinating from T4 seems like a logical progression for this thread.
 
Pretty much, a firearm is still going to look like a firearm.

It will either be bull-pupped (for short & quick pointing) or traditional (for better recoil handling and long-range accuracy).

Anything else is unlikely to matter.
It's going to have a trigger - physiologically, according to what I've seen from DOD, the index-finger operated is the most physiologically accurate mode... the only other modes I'm aware were tried were thumb trigger on back, and thumb trigger on side.

I seem to recall reading about triggers which fired on the release, rather than the pull. I envision complexity coupled with the "panic deathgrip" rendered them a dead-issue...

It's going to have a stock - folding, wire, or fixed - and those haven't changed much.

In practice, anything not moving nor scalding hot will not have a cover - because that's extra weight, and troops often just remove it anyway in the field.

Pitcatenny rails or a close functional equivalent are almost de rigeur - if it's not got an integral scope system, it's going to have a rail.

It's going to look a lot like the modern ones. And I suspect that the Lone Ranger would have no issue picking up and firing an M-16, a G-11, nor the TL10 ACR, provided it's not locked by software.

The big innovations I can see are a thumb-scan lock, coupled to a grip contact safety, allowing the trigger to work. Maybe, just maybe, liquid binary propellant.

There just aren't that many practical form factors that work with human anatomy.

Alien versions will simply put things in appropriate distances, and the grips are likely to change notably. Still, assuming you can reach the trigger, a k'kree rifle will look much like one for an Aslan.

The hiver one differs because they have no good place to put a butt-plate... but they can simply use more limbs upon it...
 
What about the Pistol equivalent?

I like the image of Han Solo and his blaster and have done a few mid-tech handguns at odd times over the years:
  • A couple of variants on 'Advanced Combat Pistol' - powerful high-tech auto pistols capable of firing somewhat effective armour piercing rounds. One concept was based on older full-power 10mm auto rounds and the other was based around a high-velocity 5mm round that was notionally somewhere between 5.7x28 and .221 fireball.
  • A deathworld-style rocket pistol (sort of crossed with the '60s Gyroget) firing explosive slugs, although this really lives in much the same niche as a snub pistol.
  • Second generation TL10-11 laser weapons, including a laser pistol (largely for a TL12 second imperium 'verse).
  • A burst firing flechette pistol - 'Far more clumsy and random than a blaster.'
  • 'Tactical Pistols' - essentially compact submachineguns.

If you want I could write some of these up.
 
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I believe T4 described "gauss augmented" ACR weaponry. Where the initial propelling energy came from a chemical reaction, but that the barrel also helped pull the projectile along to give it more penetration.
This actually has a name - in rail gun circles it's called a Plasma Armature. It's interesting because there's potentially less wear on the electrodes than with solid armature designs, but it has some knotty engineering problems associated with it. In particular you have to split your barrel into two electrodes insulated from each other while retaining enough strength to hold the pressures and stresses associated with firing a projectile.
 
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This actually has a name - in rail gun circles it's called a Plasma Armature Rail Gun. It's interesting because there's potentially less wear on the electrodes than with solid armature designs, but it has some knotty engineering problems associated with it. In particular you have to split your barrel into two electrodes insulated from each other while retaining enough strength to hold the pressures and stresses associated with firing a projectile.

That's very interesting. I guessed it was based on something that was real. I think the weapons are described either in the basic book or the Emperor's Arsenal. I think I gave away most of my T4 stuff, but still may have a book or two lying about somewhere. If you have the CDs or PDFs, then look them up. They're pretty interesting for all of T4's shortcomings.
 
Now that is a odd jump.

I would go from Auto Pistol to Advanced Combat Pistol, with both having their related magnums....

Though to be honest it probably would come out looking like a High velocity Snub pistol.

Let's compare major pistol groups in Striker, in order of TL-
TLPistol Type EffectiveLongExtremeMagazineWeightCost/Ammo Cost
59mm Magnum Rev 1(3) 4(1)10(0)6 1200 300/8
6 9mm Auto Pistol1(1)4(0)9(0)15 750200/10
810mm Snub Pistol/HEAPC(6)1(6)2.5(6)20400200/30
9Laser Pistol9(4)18(2)90(0) 5040002000/400
13 4 mm Gauss Pistol 2(4) 4(3)6(1) 15650600/20

[TD]13 [/TD][TD]Laser Pistol [/TD] [TD]10(6)[/TD] [TD]20(3)[/TD] [TD]100(1) [/TD] [TD]200[/TD][TD] 3200 [/TD][TD]3000/7000 [/TD]

The number(paren) value is range and penetration value respectively. The laser pistol weight includes the power backpack, just because they are so heavy.

From a damage/pen perspective, there are clearly 'best money can buy' options, and other options that compete more on price/weight points.

The Snub Pistol is of course perfect for short ship corridors and zero-G operations.

Also, Gauss pistols are arguably 'obsolete' by intro, but compete on not being affected by reflec. That would also be the niche of the projected ACP.

Can't really give the ACP as good or better stats as the Gauss, and the Magnum Revolver gives that up-close rifle-like punch.

So I'm thinking to give them that reflec/busting niche and better then cheaper earlier TL, we make them like those crazy Russian specforce machine autopistols, only they are now reliable thanks to TL10 material tech/caseless rounds.

https://en.wikipedia.org/wiki/Stechkin_automatic_pistol

https://en.wikipedia.org/wiki/OTs-33_Pernach


So, proposed version....

TLPistol Type EffectiveLongExtremeMagazineWeightCost/Ammo Cost
109mm ACP1(3)+2 4(2)+110(0)+0201000 400/10

FYI reviewed the MgT1E CSC family, it had the Striker 7 and 9mm versions, and two more 7mm, a carbine with short barrel for vehicle crew protection, and a rapid fire squad support role (think BAR).
 
Stats (Classic Traveller Book 1/4)

WeaponCloseShortMediumLongV. LongDamage NothingJackMeshClothReflecAblatBattle
ACR-PDW
HE-4/-4+1/+1-1/+1-3/+1-5/-34D +2/+4+2/+4+0/+3-3/-1+2/+4+2/+4-4/-3
DS-4/-4+1/+1+0/+2-2/+0-3/+13D +3/+5+3/+5+0/+3-2/+0+3/+5+1/+5-3/-1
Slugs-4/-4+1/+1-1/+1-2/+0-5/-33D +3/+5+2/+4+0/+3-2/+0+3/+5+2/+4-3/-2
ACR-CSR
HE-4/-4+1/+1-1/+1-1/+0-3/-24D +2/+4+2/+4+0/+3-3/-1+2/+4+2/+4-4/-3
DS-4/-4+1/+1+0/+2+0/+1-1/+03D +3/+5+3/+5+0/+3-2/+0+3/+5+1/+5-3/-1
Slugs1-4/-4+1/+1+0/+1-1/+0-4/-23D +3/+5+2/+4+0/+3-2/+0+3/+5+2/+4-3/-2
ACR-LSW
HE-4/-4+0/+0+0/+2-1/+1-3/+14D +2/+4+2/+4+0/+3-3/-1+2/+4+2/+4-4/-3
DS-4/-4+0/+0+0/+3-1/+2-2/+13D +3/+5+3/+5+0/+3-2/+0+3/+5+1/+5-3/-1
Slugs1-4/-4+0/+0+0/+2-2/+1-4/-23D +3/+5+2/+4+0/+3-2/+0+3/+5+2/+4-3/-2
9mm AMG
HEno-6+4+2+04D +4+4+3-1+4+4-3
DSno-6+4+3+13D +5+5+3+0+5+5-1
Slugs1no-6+4+2+03D +5+4+3+0+5+4-2
9mm Rotary
HEno-6+8+4+24D +4+4+3-1+4+4-3
DSno-6+8+5+33D +5+5+3+0+5+5-1
Slugs1no-6+8+4+23D +5+4+3+0+5+4-2
9mm rifle
HE-4+1+0-1-34D +2+2+0-3+2+2-4
DS-4+1+0-1-23D +3+3+0-2+3+1-3
Slugs1-4+1+0-3-33D +3+2+0-2+3+2-3
9mm rifle (sniper/match)
HE-4+1+0-1-24D +2+2+0-3+2+2-4
DS-4+1+1+0-13D +3+3+0-2+3+1-3
Slugs1-4+1+1-1-23D +3+2+0-2+3+2-3
ACR (Per book 4)
HE-4/-4+1/+1-1/+1-2/+0-4/-24D +2/+4+2/+4+0/+3-3/-1+2/+4+2/+4-4/-3
DS-4/-4+1/+1+0/+2-1/+1-2/+03D +3/+5+3/+5+0/+3-2/+0+3/+5+1/+5-3/-1
Slugs1-4/-4+1/+1-1/+1-2/+0-4/-23D +3/+5+2/+4+0/+3-2/+0+3/+5+2/+4-3/-2
1Mentioned indirectly in LBB4 but no stats for slug ammunition published. ACR slug round stats are published in Striker and later Traveller editions.
 
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It's detailed on page 36 of LBB:4
When firing slug ammunition, use the range modifiers of the ACR and the target modifiers and damage levels of the assault rifle. Extreme range, 1000 meters. Tech level 10.
 
Stats (Striker)
WeaponAmmoEffectiveLongExtremeTargWeightPriceDex Mods
ACR-PDW
20 HE​
20 (3) +240 (3) +160 (3) +0
1/2​
3000/500​
400/20​
6 (-2), 8 (+2)
DS​
25 (6) +250 (4) +175 (3) +0
/500​
/25​
Slugs​
20 (4) +240 (3) +160 (2) +0
/500​
/15​
ACR-CSR
20 HE​
37 (3) +275 (3) +1120 (3) +0
1/2​
4500/500​
2000/20​
6 (-2), 8 (+2)
DS​
50 (6) +2100 (3) +1150 (3) +0
/500​
/25​
Slugs​
37 (4) +275 (3) +1120 (2) +0
/500​
/15​
ACR-LSW
40 HE​
37 (3) +375 (3) +2120 (3) +1
2​
6000/1000​
1500/40​
6 (-2), 10 (+2)
DS​
50 (6) +3100 (3) +2150 (3) +1
/1000​
/50​
Slugs​
37 (4) +375 (3) +2120 (2) +1
/1000​
/30​
AMG
100 HE​
40 (3) +480 (3) +3150 (3) +1
8​
8000/2500​
4000/100​
6 (-2), 10 (+2)
DS​
50 (6) +4100 (3) +3150 (2) +1
/2500​
/125​
Slugs​
40 (4) +480 (3) +3150 (2) +1
/2500​
/75​
9mm Rotary
1000 HE​
40 (3) +880 (3) +6150 (3) +3
16​
20000/25000​
10000/10006 (-2), 10 (+2)
DS​
50 (6) +8100 (3) +6150 (2) +3
/25000​
/1250​
Slugs​
40 (4) +880 (3) +6150 (2) +3
/25000​
/750​
9mm Rifle
10 HE​
30 (3)60 (3)90 (3)
1​
3000/250​
350/10​
6 (-2), 8 (+2)
DS​
45 (6)90 (3)
/250​
/12​
Slugs​
30 (4)75 (3)90 (2)
/250​
/7​
9mm Match/Sniper
40 HE​
80 (3)150 (3)90 (3)
1​
6000/250​
2000/10​
6 (-2), 8 (+2)
DS​
50 (6)100 (3)150 (2)
/250​
/12​
Slugs​
40 (4)80 (3)150 (2)
/250​
/7​
 
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Doesn't Snapshot also have the same inference for the ACR? I can't remember off hand.

My ACR thoughts; most of the players I ever gamed with preferred SMGs, autorifles, or some energy weapon variant. I always figured the ACR was probably the mainstay weapon for non ship's troops. That is the army probably had "heavy infantry" units armed with HEWs like battle dress marine units, but simply because they were a larger organization, and probably had more jobs to do than the marines, they probably went for a cheaper alternative on non frontier worlds (worlds deep enough within the Imperium that they weren't on the radar for invasion).

Again, just my view here, so as you guided your players or played a session, and came across a variety of military NPCs, odds are they were probably armed with "high tech" or higher-tech versions of the ACR, and army/marine units in CA or BD toting some plasma or fusion gun (or even laser weapons) were probably in places like the Solomani Rim, the Marches and so forth.

Further, that as per my EMG thread ("electromagnetic gun") the ACR was probably a good cheap alternative for non-aligned or worlds that had ambigious allegiance, or wanted to supply their soldiers with something that had punch, and with proper augmentation could at least put a dent in units with BD or CA.

And as per posts in the past, the Aliens pulse rifle was a good example of an ACR.
 
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