A popular platform for building DIY “zip guns” is the humble staple gun that is easily obtainable at your local office supply store. This is a four shot model (not sure if that means 4 shots fired all at once, or four barrels each fired on a single pull of the trigger, like the famous COP .357 Derringer). The reader who sent this in explained the name he gave it …

Yeah, another ubiquitous staple gun derivative. This version is a 4 shot .410 that sometimes masquerades as a caulking gun, hence the name, the Kaulkinator or K-441. Still untested with a full load. This has been designed for 2.5″ shell and slugs. An inertial pin on a heavy spring keeps things safe. It’s a little big, but for a first attempt at a DIY (non-3d print) firearm with only a small drill press to work with, I think it worked out well.

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  • USMC03Vet

    Incoming NFA tax stamp requirement for stapler owners….

    • echelon

      And you can bet if they did all of the stapler owners in this country would roll over and hand over the dough.

      Wouldn’t want to be “non law abiding” now would we?

    • dan citizen

      I’m doing an office supply dedicated NFA trust.

    • If the barrel is rifled, you don’t need the tax stamp.

  • MothersAgainstBitsofTube

    Why haven’t our politicians closed the stapler loop-hole? In my opinion it is simply beyond the pale why such devices are freely available to the general public without any registration or regulation.


  • Ph43drus

    What is the deal with the pneumatic fittings?

    • Peter Larson


    • Ratus

      Because Race Gun!

  • David Huynh

    i would like to see this in action, i would be to scared to shoot it.

  • McFortner

    I’m afraid to even watch a video of it firing.

  • Secundius

    I’m sure that there somebody Stupid Enough, too one.

  • me ohmy

    adds an entirely new meaning to “staple gun fight”

  • mechamaster

    Bringing staple to the gun-fight.

  • Mystick

    Wow, if it fires all four at once, that may be a wrist-breaker… especially with an inconsistent grip due to the apparent trigger mechanism.

  • Bubba

    I’m gonna need some more info about this.

  • mosinman

    look! it’s an evil ghost gun!

  • steveday72

    I thought shotgun pistols were classed as NFA items? (Though the. 410 was exempt because there was/is a revolver round with the same seating dimensions?)

    Could just be my memory playing tricks with me though – CFS/ME screws with the brain

    • B.

      I believe if it has a rifled barrel it’s not considered to be a NFA destructive device or any other weapon.