The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    The Big Pipe at Home: TFB Reader Makes a DIY 37MM Launcher

    The DIY firearms world has seen plenty of cool creations over the years. We’ve seen steady advancements from the largely self-driven community of builders in terms of durability, functionality, convenience, and of course creativity. Many of you will know Stubbs from some of his previous creations we’ve covered like his Mosin Nagant featuring a folding stock, or his double-barreled, double-feed AR-15 rifle. This time Stubbs has brought a DIY 37mm launcher with him. Today we’ll look at what Stubbs has done in order to accomplish this feat and explore if it might be possible for you to do this yourself.

    More of Stubbs’ Creations @ TFB:

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    So why design, print, and build out your own 37mm launcher when so many already exist on the open market that takes the guesswork out? Aside from the obvious “because I can” that a lot of 3D printers use to fire up their 3D printers, Stubbs actually wanted a few different features for his own launcher that none of the other printable launchers did.

    The only reason I set out to make this, with another printable launcher already coming out around the same time, was that the Thump N’ Grind was not compatible with everything I wanted. My PSQ-18 laser device for example fits the M203 style handguard with a small adapter I made, and since the barrel swings out sideways like an M320 it is compatible. The TNG uses a revolver cylinder swing out style mechanism that would not be. I also have published a picatinny handguard. My design is less bulky and more in line with previous launcher styles, but the TNG is meant to be a complete departure, to compliment a 3d printed firearm and it does so well.

    So with that short explanation out of the way, what is Stubbs’ latest creation called? In line with his other asinine designations for his creation, Stubbs is taking a book out of the film “Pulp Fiction” and calling this one “The Pipe Hitter.”

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    Compatibility and Materials

    The Pipe Hitter isn’t called as such solely because of the pop culture movie reference. The 3D printed 37mm launcher actually uses a common pipe for the barrel that you can buy at any hardware store. Other off-the-shelf components include commonly available springs, a nail to act as the firing pin, a fender for the reinforced breech face, and two bushings to prevent wear for the swing-out hinge. Lastly, and probably most importantly, the receiver itself is made from two 3D printed halves and bolted together with common hardware.

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    The launcher is made to mount directly to an M16 or M4 handguard with washers and 1/4-20 bolts. Stubbs initially designed a barrel nut mount similar to an M203s but that would have required fabricating metal parts. Stubbs also designed a Picatinny mountable version that as far as I know has yet to see the light of day. 3D printable parts would not withstand the heat of being mounted to the barrel and using the cheap regular handguard or a railed forend is simple. According to Stubbs, there will be future additions to the standalone version, like a proprietary adjustable front sight better calibrated for the shorter range.

    Wait, Is that LegaL?

    A lot of you are probably scratching your heads if you’re unfamiliar with 37mm launchers and the like. Stubbs is no stranger to dancing around the NFA all he can but this one is actually completely legal as 37mm launchers are considered “signaling devices” (provided non-impact based ammunition is used with them) as opposed to a “destructive device” which would necessitate a $200 tax stamp. A lot of people usually skip the 40mm route due to a combination of cost, availability, and legality, so 37mm launchers are far more popular and tend to have more commercially available ammunition for them.

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    As mentioned above, 37mm launchers are signaling devices and are exempt from any and all firearm laws unless possessed with impact-based ammunition. The 37mm ‘riot’ ammunition can even be collected and owned by itself for those without launchers, but the possession of both constitutes a Destructive Device. If you attempt this, please be sure to double-check that you’re not going to get yourself in trouble with the print. Even if you did want to use any impact-based devices in this launcher, you couldn’t because it can’t handle the pressures according to Stubbs.

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    Some 3D printed Ammunition


    The Pipe Hitter is a very interesting creation that I feel once again expands on the great opportunities that 3D printing technology has afforded firearms owners and enthusiasts. Stubbs was able to adapt existing designs and technologies to suit his needs and now he can presumably move on to bigger and better things. Stubbs had one more final thing to say before he wrapped up his explanation of The Pipe Hitter:

    As with all things horrible in my quest to finish a proverbial Hobart’s Funnies of oddly specific guns that perform functions requested by those far outside of the mainstream, if I hear enough noise I will make a double barrel version.

    Please give him the strength and courage to carry on. As always, your thoughts and comments are always welcome. Do any of you who 3D print out there find this interesting? Is there perhaps possibly room in the future for designing and fielding your own 3D printed 37mm signaling ammunition? Let us know down below!

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

    The Pipe Hitter: TFB Reader Makes a DIY 37MM Launcher

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