A DIY Submachine gun

A reader emailed me these photos of a homemade submachine gun built by man in Romania from the plans of Luty’s infamous book. It is chambered in .32 ACP and fires at a rate of 550 – 600 rpm.

Improvements of the original Luty SMG are ergonomic maple knotwood grip, forward grip/extended magwell, ligher bolt, heavier mainspring and a glock-style feed ramp.

On of these days I would like build a legal blank firing submachine gun.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • AB

    I’m reading the pdf of the Luty manual right now and there is a great deal of room for improving the design. With basic machining skill and a willingness to try something new, the design can be turned into a carbine type with extended barrel and collapsing stock. Picatinny rails are easily machined as the design is available almost everywhere.

    This is the kind of information governments fear the people have. Not because of felons getting access to guns, not because of a lone machinist making a one-off on a lark, but something more insidious.
    The fact that when those in power try to push us as a people too far, armed insurrection is no longer a vague threat but a quantifiable reality.

  • hojo

    @AB well said.

  • Fiftycal

    obviously the answer is to register and TAX machine tools. And appoint “inspectors” to monitor the use of those registered tools.

  • what the heck is that laser/block of wood thing that is sitting on top?

  • Bob

    A.B. — I salute your comments.

  • Martin

    @ AB, so right you are.

    I’ve always wondered how you could make a rifled barrel without specialized equipment. I’m familiar with the different processes, but I’m still curious.

  • AB

    Looks like an old school laser dot and 1x scope.

    Several of my books actually discuss how to ream a barrel to give it a type of rifling, but they require a lathe and heavy modification of a machine tool part in order to perform such an operation.

    What do you think of showing examples of the books in order to give people an idea of how easily these devices are made?

    • AB, I don’t mind links being posted to individual pages of the book, but not the whole book as it is copyright.

  • mr lorenco _(republic of kosovo)

    @ AB

  • I read the Luty manual a few years ago and was intrigued. I searched, but was unable to find a semi-automatic version. I have no use for a sub-gun because of the legality issues; however, I think (and I would research this before doing anything to make sure) that it would be legal (in my area) to make a semi-automatic firearm at home for personal use. I don’t think it would be legal to build them for sale without proper lic. Does anyone here know? keep in mind I would still recheck with a lawyer before I started, I’m not dumb enough to risk jail time by getting legal advice on the internet.


  • Huh?

    Why? AKs cost like $6 in Romania.

  • @Martin, I could never make my own rifled barrel, and Luty assumes you don’t have the machinery/knowledge to do it. But if you purchased a dozen generic barrels (pistol or rifle) at a gun show and included them in a Luty build instead of the hydraulic plumbing, then you would still remain anonymous while gaining range and accuracy over Luty’s original instructions.

  • wrangler5

    Colonial gunsmiths did it with wooden machines, pulling single tooth cutters through a bore, adjusting for depth of cut with paper shims. (I think there’s a video from Colonial Williamsburg that shows the equipment and the process – I saw it on VHS years ago, and assume it’s available on DVD now.)

    More modern equipment can be made by a reasonably competent machinist. Here’s a link to an old thread on the Practical Machinist forum, which has pix of one machine and links and references to lots of other info.

  • wrangler5

    Sorry, forgot the link (and don’t see an edit button) – see http://www.practicalmachinist.com/vb/gunsmithing/home-built-rifling-machine-126815/

  • Kristopher

    Martin: Same way it was done in the 1600s.

    Embed a chip of hard metal in the side of a brass rod. Make a mechanism out of wood to run the rod in and out of the bore, while slowly turning it. A helical track engaged by a single toothed sprocket attached to the rod will work.

    Use shims to force the hard cutter against the inside of the bore. Cut a shallow rifle groove. Add more shim. Repeat. When done, rotate the barrel a bit and start the next groove.

  • Jack Else

    What’s the title of the book?

  • The book, “Improvised Weapons of The American Underground,” has blueprints for a .45ACP submachinegun that uses grease gun mags. Hehe, the book had a lot to do with how I ended up with my nickname.

    IIRC, Delta Press (www.deltapress.com) has this book, and a few other build-your-own-machinegun type books. Just to be safe, I’ll remind everyone that building full-auto firearms is very illegal to everyone that doesn’t have special ATF licensing. The books/plans on how to make them are legal though, at least at the moment.

    I’m somewhat shocked to see that the book is carried by Amazon too.

  • Damn, did they include a test firing video? I would love to see this gun in action.

  • Oh and the extended mag well is part of the design of luty’s .32 cal machine pistol.

  • Hey, I am wondering if you could get back with the person who built it and ask if they could upload on youtube a test firing video? I think we are all curious to see how this gun would function.

  • rjm

    I will email him and see if this can be arranged.

  • rjm

    Oh and to others;
    That IS a laser sight, and the finish is Parkerizing done in a zinc coated
    drywall tub, thus the greenish tint.

  • @rjm:

    Ok, you can message me on youtube for any updates, I am “unknown1730” on there.

  • @rjm:

    Got anything response back from him?

  • The Luty design is a bit off and the safety factor is really low. I bought the book but wont build it, its just not safe under any condition . If Im going to build something like this I want it to be legal and safe. At best the book is good for understanding the way a basic a machine gun works . WHICH IS WHAT THE AUTHOR HAD IN MIND.

    • Marder

      It is perfectly safe since the sear is built with its axis in front of the bolt catch. With this, the gun cannot self-discharge unless something or someone presses the trigger : any additional safety is superfluous.
      The second possible source of danger is the lack of heat treatment and relative thinness of the barrel, but that really is of no concern for .32 ACP, or even .380.

      The book is intended to be used as a building guide for a functional, if minimalist, weapon and succeeds at it (i’ve built a few variations based on this design and they work no matter what).

  • Rob

    this is not the Luty design from his book, it is from his website actualy. I know due to the trigger, and its in .32, one of his designs is in .32/.380. The designs on his website are free-acess. He wrote the book to show the Brit Goverment they cannot ban guns completely. I will put his website up due to how I belive in information should be presentable to everyone. It is a simple design. I should warn you, if you live in the U.K. and download one of his designs the police will likly raid you home, like in the past. http://thehomegunsmith.com/index.html

  • mhm

    Just for all of you’rs information, guns aren’t “completely banned” in the UK. You can own Semi-auto rimfires, bolt action centerfires and just about any type of shotgun. Pistols are more difficult to get and you need a very good reason to be given a license.

    • Cymond

      OTOH, aren’t the “12/24” style pistols just the same as buying a rifle?
      For those that don’t know, “12/24″ refers to a firearm with a 12″ barrel and 24″ overall, much like the US requirement of 16″ barrel and 26” overall. 12/24 pistols are built with extended barrels and a rod coming back from the grip. I can’t seem to find a picture easily.