Can a 9mm Sten be modified to fire .45 ACP?

Discussion in 'Research' started by JadeX, Jan 30, 2016.

  1. Samurai Jack

    Samurai Jack Active Member

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    @Cave Troll It wouldn't be an ideal situation, but a machinist could continue the process of forming the bullet. A cap is stamped out of a sheet of metal, the cap is heat treated and stretched into the full casing shape. A .45 casing could be compressed, stretched, and cut down to a .35.

    I mean, we are talking about the nonexistence of firearms and ammunition, of manufacturing processes for 50 years. It could be a situation where there are hundreds of thousands of rounds for a dozen existing rifles, and zero rounds for 150 newly built rifles. Melting the casings down would mean the need for a stamp to make the new bullets. New rounds require a complete creation process. Old rounds could only require a portion of it.
     
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  2. Cave Troll

    Cave Troll It's Coffee O'clock everywhere. Contributor

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    I see, that sounds, sound enough. I think the guy with an old cap and ball pistol or rifle would have the easiest time fairing under such conditions, as he could utilize the materials and cast lead balls or riffled rounds in a mold while cooking with a campfire. Granted they would sacrifice accuracy and range for utility, and extremely low rate of fire. But he would never be with out bullets. :p
     
  3. nippy818

    nippy818 Senior Member

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    Firearms are extremely easy to build. In Pakistan they build aks from old cars and scrap metal. The sten gun is such a simple design he might not even need plans. if he knows even a bit about machining your mc could easily build a semi or full auto weapon. I have friends that build ARs from 80 percent lowers.
     
  4. Cave Troll

    Cave Troll It's Coffee O'clock everywhere. Contributor

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    AKs from old cars and scrap. That is some Metro 2033 level shit right there. :p I saw a couple of different vids a while back of 'homemade' guns. The first was a guy that made a Steam Punk .22 Gatling gun that was hand crank. The other a guy built a Steam Punk Mosin Nagant. So in theory you can really make a gun out damn near anything as long as the materials are durable enough and you have some inkling of what in the hell you're doing. :p
     
  5. nippy818

    nippy818 Senior Member

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    Look up zip guns and insurgent weapons. Its amazing how creative people can get
     
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  6. JadeX

    JadeX Senior Member

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    Okay, so, I've got the ammo question out of the way - my insurgents can cast their own 9mm casings and re-use the primers, powder, and bullets from the .45s to make an acceptable makeshift ammunition.

    A side-issue, however: The Sten's magazine. By all accounts I've read, the Sten's magazine was one of its biggest flaws. Now, while my characters do not yet have access to any Thompson SMGs, they do have a few Thompson magazines. Being that the Thompson's magazine was far superior, might my insurgents be able to build a new 9mm magazine based on the Thompson design? (essentially a "scaled-down" version for 9mm)

    I don't see why not, and doing so would greatly reduce the amount of problems the Sten's magazine was known to cause (like jamming and such).
     
  7. Samurai Jack

    Samurai Jack Active Member

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    So, the Sten uses a double stack, single feed design: two staggered columns of of bullets in the magazine until the top, where the next round chambered is centered in the magazine. The Thompson uses a double stack, double feed: two staggered columns of bullets in the magazine all the way through feeding.

    The issue is actually getting the round into the barrel. Single feed will jam the bullet straight into the barrel. Double feed funnels the round into position. The Sten isn't designed to maneuver the round into position like a Thompson is. So, the answer becomes not really, unless you redesign the Sten's barrel to match the Thompson, which you certainly could do.

    Or, you could redesign the magazine to be a single stack, single feed. The issue with double stack was the upward force of the rounds bending the feed lips out of place. And a problem with a lot of modern staggered stacked magazines in general is the need to keep them clean and serviced on a regular basis. Single stack single feed gets rid of those problems, the trade off being round capacity. India modified Sten magazines that way, gaining performance but going from 32 rounds to 19 rounds.
     
  8. Shadowfax

    Shadowfax Contributor Contributor

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    The reason resistance group used Stens was because they were supplied to them by the allies, not because they made them.

    The reason why the Sten was designed was to mass-produce a gun, almost any gun, to re-equip the British Army, which had lost a lot of weapons in France. It had to be cheap, and quick to produce. In order to achieve this, a lot of parts that would have been machined in a normal weapon were pressed out of sheet steel. Once you've got the dies made to go into the press, you just bang out the parts very quickly.

    The key words are "Once you've got the dies." The dies need to be manufactured out of very high quality steel, and machined to very fine tolerances...otherwise, by the end of a run, the parts are coming out a different size to the start of a run, and you can't assemble the gun because the parts are outside design tolerances...or things start falling apart at crucial times.

    Something else to consider is that pressed parts need to be manufactured on a power press. These are big buggers...just Googled power press, and they were talking about a 2000 tonne monster. I've never worked anywhere with something that big, but small ones don't just fit in your garden shed, and you won't pick one up in Wal-Mart!
     
  9. JadeX

    JadeX Senior Member

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    I don't doubt you, particularly because it sounds like you have some experience and know your stuff, but as they say on Wikipedia... [citation needed].
    I've done some research on the Sten and haven't come across anything suggesting that such a huge piece of machinery was required. And I do know that, yes, while the Allies did supply Stens to some resistance groups, the Polish resistance did build many of their own as well. Not to sound argumentative or anything, just "trust but verify".

    In any case, even if you are right about that, I do in fact have a backup plan: The BÅ‚yskawica. While less known and harder to spell/pronounce, it seems to offer everything I had originally found in the Sten, but simplified even further. So even if the Sten idea falls through, I have the BÅ‚yskawica to fall back on.
     
  10. JadeX

    JadeX Senior Member

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    Another idea, unrelated to any of this stuff, but I'll ask here instead of making a new thread (since I've already got several people here who know about the subject)

    I'm also interested in having my characters manufacture FP-45 Liberators since, apparently, they're really freakin' easy. I found a scratch build thread on a firearms forum and it's definitely within the capabilities of some of my characters.
    (they'd be issued discreetly to individuals,to carry out small lone-wolf attacks, making it easier to spread the revolution and prove the willingness of new recruits)

    Thing is, the Liberator fired from a 4-inch smoothbore barrel, which meant it only had an effective range of 1 - 4 yards.

    But what if they found some extra M1911 barrels? Cut an inch or two off and use them in the Liberators, improve the accuracy a little bit. They both fire the .45 ACP cartridge (found a use for these .45s!) so the barrel is already the right size. Should work fine, right?
     
    Last edited: Feb 5, 2016
  11. Shadowfax

    Shadowfax Contributor Contributor

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    Looking at the two guns, the M1911 barrel doesn't look particularly interchangeable with the FP-45. But, why not just use a piece of steel tube (first Google hit found 50mm OD/1.5mm wall thickness = 47 mm ID - if these guys are any good, they'll know the best sources and how to maybe ream out a smaller OD with thicker walls) and make an imitation Buntline Special. OK, no rifling means it'll never be a target shooter's dream, but you don't want to go for long-range firefights when all you've got is a single-shot weapon that takes forever to reload.

    Thing is, though, the chief object of the Liberator project appears to have been letting the Germans know that thousands of them had been dropped for resistance forces to use, and leave the Germans paralysed with fear. There's no record of them being used (after all, that single-shot use is a bit of a bummer if the guy you just shot wasn't the only German around - or if the inaccuracy meant you'd only winged him, and he now starts shooting back!) and Generals Eisenhower, Stilwell and MacArthur all opposed the plan, so fewer than 25,000 out of half a million were actually distributed.
     
  12. Samurai Jack

    Samurai Jack Active Member

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    Given the context of your story, yeah, it would work. There's the caveat of "with modification," but, that seems to be the theme of the thread.

    I thinking along the lines of Guy In Charge walking up and telling Metal Worker Me, here's some plans for a breech loading, single shot pistol. Here's a box of a hundred barrels. Make it work. I'll see you next week.
     
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  13. mg357

    mg357 Active Member

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    I am not 100% that it could be done. But the M3 Grease-gun used by American forces during WWII had a special kit where it could be converted from .45 caliber to 9mm caliber.

    I also have a second suggestion what if they find a cache of parts and assembly instruction manuals for Thompson submachine guns? all they would need to do is follow the instructions in the manuals and assembly the guns.
     
    Last edited: Feb 6, 2016

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