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Old 07-19-2020, 11:41 AM   #1
Tinman
 
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Default Help stating a Firearm: The American 180 .22LR SMG

I'd like help stating out the The American 180 .22LR Submachine Gun (A Swarm of Angry Bees)

The American 180 is a .22 rimfire submachine gun that fires at 1200-1500 rounds per minute or more, and feeds from drums of 177 to 275 rounds capacity. While it makes a great recreational machine gun, it was actually initially developed with law enforcement sales in mind. The notion was that the .22LR cartridge posed a minimal danger of overpenetration and was extremely easy to control, and the many repeated hits that could be made with the American 180 would make up for its lack of ballistic effectiveness. And that's not necessarily incorrect.

Several law enforcement agencies did actually buy the guns, and one police shooting involving one is documented, from 1974. It never became really popular with police agencies, though, and production basically ground to a halt in 1986 when it became impossible to manufacture new machine guns for the civilian market.

Here's the video from Forgotten Weapons:
https://www.youtube.com/watch?v=J50N5lQoAFw

Last edited by Tinman; 07-19-2020 at 12:00 PM.
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Old 07-19-2020, 01:47 PM   #2
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

I'm not sure what you need help statting - there are several examples of .22LR weapons in High-Tech and the two Pulp Guns series, some pistols and some long arms. All of the long arms have Damage 1d+2 pi-, Acc 3, Range 75/1500, Rcl 2, or something close to those numbers. 1200 rounds per minute works out to RoF 20. Cost and weight will be based on real word cost & weight; bulk is generally based on weight. Weight looks to be 5.75 empty; 10lbs with the 176 round drum; about 12lbs for the 275 round drum. That suggests a Bulk of -5 (some weapons this heavy have Bulk -6, but this one has most of the weight in the drum and a much shorter barrel; a Bulk -4 might even be appropriate). ST is probably 10†, maybe 11†. The Tommy Gun has Bulk -5, ST 10†, which sounds about right for this gun to me.
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Last edited by ericbsmith; 07-19-2020 at 02:22 PM.
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Old 07-19-2020, 02:20 PM   #3
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

Damage for a rifle-length .22 LR weapon should probably be 1d+2 pi-; that's what the AR-7 in HT does, while most of the pistols do 1d+1 pi-. For Bulk, I found a generic trend of barrel length determining Bulk, where a 0.1 yard barrel would be Bulk +0. A stock causes a -1 to Bulk. For the American 180, it has about at 0.5 yard barrel, for Bulk -4, and a stock for a further -1, for a total of -5. Drum magazines can influence Bulk, although from images the drum on this one is low-profile enough I wouldn't bother. The short barrel version (a little more than half the barrel length) would be around Bulk -4, maybe Bulk -3. At Bulk -4, it's probably alright for it to still deal 1d+2 pi- (the AR-7 is also Bulk -4), but if you build it as Bulk -3, I'd probably go with 1d+1 pi- (making it consistent with giving a pistol a stock).
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Old 07-19-2020, 08:20 PM   #4
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

Quote:
Originally Posted by ericbsmith View Post
I'm not sure what you need help statting

- All of the long arms have Damage 1d+2 pi-, Acc 3, Range 75/1500, Rcl 2, or something close to those numbers.

-1200 rounds per minute works out to RoF 20.

- bulk is generally based on weight. Weight looks to be 5.75 empty; 10lbs with the 176 round drum; about 12lbs for the 275 round drum. That suggests a Bulk of -5 (a Bulk -4 might even be appropriate).
Well, that's exactly the kind of stuff I wanted advice on stating.
Thank you.
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Old 07-19-2020, 08:34 PM   #5
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

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Originally Posted by Tinman View Post
Well, that's exactly the kind of stuff I wanted advice on stating.
Thank you.
No problem. The thing to keep in mind with all I did was mostly just comparison to other similar guns. RoF is just Rounds per Minute / 60, since Rounds per Minute is generally calculated based on continuous fire (which few real world guns can actually sustain due to reloading and barrel over-heating; even water cooled chain fed machine guns will risk overheating after a minute of continuous fire). For weight I just googled the weight of the gun, and hoped the source I found was correct (it looked close enough for me).

Bulk is the only really debatable stat, since it's based on an esoteric combination of weight and barrel length/weapon size; essentially how hard the gun is to conceal.

It's much harder to extrapolate weird or esoteric weapon stats, since there are fewer points of comparison.
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Old 07-20-2020, 06:23 AM   #6
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

Quote:
Originally Posted by ericbsmith View Post
No problem. The thing to keep in mind with all I did was mostly just comparison to other similar guns. RoF is just Rounds per Minute / 60, since Rounds per Minute is generally calculated based on continuous fire (which few real world guns can actually sustain due to reloading and barrel over-heating; even water cooled chain fed machine guns will risk overheating after a minute of continuous fire).
Not Vickers guns and close relatives. Their rate of fire in the long term is slowed a little by reloading and mostly by having to change barrels every 15,000 rounds or so due to wear, as long as they have ammo, water, and replacement barrels they can fire indefinitely.
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Old 07-20-2020, 11:31 AM   #7
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

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Originally Posted by Rupert View Post
Not Vickers guns and close relatives. Their rate of fire in the long term is slowed a little by reloading and mostly by having to change barrels every 15,000 rounds or so due to wear, as long as they have ammo, water, and replacement barrels they can fire indefinitely.
....or for about 4 hours. That's a record from WWI.

For what it's worth my pre-Internet memories recall stories of the American 180 (equipped with a laser pointer even bigger than the one from Teminator) beign used to write the firer's name in cursive with one long burst and cutting a VW in half like it was a saw.

If that last sounds improbable it might be but old VWs were much lighter than new ones. Under 2000 lbs.

Anyway, the 180 might work better than usual in long bursts.
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Old 07-20-2020, 06:10 PM   #8
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

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Originally Posted by Fred Brackin View Post
....or for about 4 hours. That's a record from WWI.

For what it's worth my pre-Internet memories recall stories of the American 180 (equipped with a laser pointer even bigger than the one from Teminator) beign used to write the firer's name in cursive with one long burst and cutting a VW in half like it was a saw.

If that last sounds improbable it might be but old VWs were much lighter than new ones. Under 2000 lbs.

Anyway, the 180 might work better than usual in long bursts.
I've heard it's got almost no recoil & is very controllable. (It looks that way in the video.)

I'm going to try & have my gadgeteer for a pulp-era action campaign make one. I hope it will prove effective in combat.
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Old 07-20-2020, 07:38 PM   #9
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

I would give it effective recoil 1 for full auto fire.
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Old 07-21-2020, 05:13 AM   #10
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Default Re: Help stating a Firearm: The American 180 .22LR SMG

[QUOTE=Fred Brackin;2334307]....or for about 4 hours. That's a record from WWI.
I think the WWI episode was more like 8-10 hours for a battery of 10 guns with no failures. In 1963 when they were going out of service they had a huge pile of ammo that was going to be dumped so they took a Vickers and fired it continuously for a week, aside from breaks to replace the barrel. It was still within operating specs at the end and it had fired millions of rounds. A good cooling system, a modest rate of fire, and a lot of mass lets you make a very reliable gun. Modern GPMGs trade sustained firepower for lighter weight.

Quote:
For what it's worth my pre-Internet memories recall stories of the American 180 (equipped with a laser pointer even bigger than the one from Teminator) beign used to write the firer's name in cursive with one long burst and cutting a VW in half like it was a saw.

If that last sounds improbable it might be but old VWs were much lighter than new ones. Under 2000 lbs.

Anyway, the 180 might work better than usual in long bursts.
It would, yes - the .22LR isn't very energetic and is low-pressure enough that it's also fairly efficient (for a gun), so unless the barrel is very light it'll heat up relatively slowly.

While in a GURPS write-up it would still have Rcl 2, it's also a calibre that will have very low recoil and be very controllable so writing with it shouldn't be hard with a little practice. A new form of annoying to remove graffiti!

Quote:
Originally Posted by Juca View Post
I would give it effective recoil 1 for full auto fire.
I wouldn't. It fires fast, but not super fast, and Rcl 1 has potential for problems. Sure, they probably won't show up with 1d+2 pi- damage, but it's still risking opening a can of worms.
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