Simple and compact low-cost DIY submachine gun prototype

Here are pictures of a neat little submachine gun prototype sent in. It uses minimal components and can be constructed with very basic tooling in short order. The builder made the example pictured as a non-firing replica for obvious legal reasons.

The criteria was for a design which can match similar commercial counterparts in terms of compactness, durability and aesthetics whilst being infinitely cheaper, quicker and easier to produce. It uses Sten mags, a spring from a grease applicator tool, standard lock collars and a rubber bicycle grip among other easily obtainable bits.



It strips down to only nine main components which are all housed in a single receiver tube. Internal arrangement is Illustrated below:



Some may recognize it as being a basic simplified copy of the Texas made MP2 SMG seen wielded by Arnold in the film Raw Deal.



Edit: Here is a PDF detailing it’s construction.


  • Stephen Beat

    Can anyone else say ‘Sten’! LOL (I’m sure I am being facetious, but it does look like all they have done is moved the trigger forward and dispensed with the stock!)

    • iksnilol

      Open bolt blowback SMGs can only be made in so many ways. So the similiarity is no surprise.

  • Tassiebush

    It’s like the illicit offspring from an affair between Mrs Welrod and Mr Sten. The magazine forming part of the grip especially reminds me of the welrod. No idea how it’d shoot with a functioning version but it has considerable merit as a clandestine gun given how concealable it is and how easily it could be made.
    Improguns is always a delight!

  • claymore

    Doomed by the use of the absolutely terrible sten magazine.

    • Iggy

      As I recall that didn’t doom the sten

      • claymore

        Apparently you have never had to use one LOL. Wartime they made do with it.

        • Iggy

          I’m not saying it was amazing, but the sten was good enough to be copied by multiple insurgencies and the Germans, so it did something right.( though I’m biased as an Aussie and still think the Owen was the best cheap subgun of the war) And this one has the advantage of better concealability.

          So as long as it can be put together in a shed without having to source any outside gun parts and can spray lead it does the job it was designed for.

          • Sianmink

            If you’re sourcing a pre-manufactured magazine why not a Glock 33 rd instead, or at least uzi?

          • iksnilol

            Because Glock mags can be expensive, hard to get and a female dog to fabricate. Especially in restricted areas. Manufacturing straight Sten or Uzi mags is way easier.

          • Sianmink

            Now that magpul is making glock mags, they’re pretty affordable.
            sure making Sten or Uzi mags is easier, and that’s a plus if you’re actually folding and welding them yourself.

          • iksnilol

            Eh, I am leery of Magpul. + just because it is common in the us doesn’t mean it is common around the world. That’s how you gotta think in regards to insurgency guns.

          • Tassiebush

            I think the point is that in most of the world large mags aren’t commercially available to regular folk while designs for Sten mags are pretty readily available.

          • claymore

            But gets you killed when it jams from poor magazine design?

        • HenryV

          Do you cringe every time in a film you see somebody holding the magazine when shooting? Because you know if they were shooting for real life it would cause a jam.

          • claymore

            For sure.

  • Mongo

    The tubing will tear out where the screws retain the front trunion. Not a safe design.

    • Jeffbob

      The old Luty and Minuteman designs use the same screw set up. They will take more wear than threading but will last ‘long enough’.

    • patrickiv

      I agree but it could easily be strengthened by keeping more material forward and rear of the holes. Threading of the tube and trunnion would be better but would require a much more expensive tap and die. Actually I don’t see why they don’t just weld the barrel in place.

    • Ken

      You can countersink the trunnion and dimple the sheet metal into it like on the front trunnion rivets on an AKM. Granted, this is a straight blowback and that area would bear more force than on the locked breech AKM.

      You could always just weld it.

    • jrt 82

      It only has to last until you can “pick up” a new system.

  • HenryV

    Will Ruger have their version ready for SHOT Show 2016 or will we have to wait for the NRA Convention?

  • iksnilol

    I like it.

  • WoodWorm

    Google search ‘Practical scrap metal small arms vol.8’ if you want full plans. 🙂

  • Southpaw89

    You could get creative with a few more pieces of scrap metal and make some kind of telescoping or folding stock for it as well, don’t think it’d be that hard and would greatly improve the usefulness of the design.

  • Vhyrus

    Link plans please…. uh, for informational purposes only, of course..

    (Oh, and can you make them Glock mag compatible?)

  • gunsandrockets


  • Noir

    DIY vz.48 Sa23/24/25/26 apparently.