Open Source the GMG (Fully Auto Airgun)?

The makers of the GMG .22, a fully automatic air gun, are considering open sourcing the design. Sales have not been good and they think there could be more money selling plans, kits and parts than fully assembled guns.

I think they should open source the design and release the plans and any CAD models under a Creative Commons license.

If they can create a community of builders and modders there could be a profitable business in selling parts, kits and upgrades.

This business model has worked well in the hobbyist electronics market where mini-industries develop around supplying parts and kits for open source hardware.

The company is running a poll on their website, asking if people would be willing to buy parts, rather than an entire 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.


  • James Martinez

    Anyone know the specs on them? It’s an interesting design and idea, but honestly I have an airgun that shoots ~800 fps and this kind looks like a hopped up airsoft. And at $750 I would just buy an ar/ak.

    • bbmg

      Website says 600+ FPS with 16gr lead ball, that’s enough to pop a rabbit at 50 yards.

      • D

        Roughly 17 joules, then; a .22’s low end is around 100 joules for comparison.

      • bbmg

        In the UK any air rifle with over 16 joules of muzzle energy is considered to be a firearm which needs a police license, and therefore the vast majority of airguns are sub 16 joules, but these are routinely used to kill small game such as rabbits and crows at ranges of 30-50 yards, so while power is nowhere near a 22 rimfire, it still isn’t something to be taken lightly.

        Another consideration is the weight of fire, a single 7.62mm bullet won’t make much impression on a brick wall, but an M240 on full auto can cut a man sized hole through it. In the same way, an airgun capable of automatic fire can be much more devastating than a single shot device.

  • bbmg

    I guess the biggest problem is that the demographic that would be most interested in a full auto cartridge fed airgun is not the one with cash in hand.

    If you want an air powered auto, you can make a ghetto one for a few bucks. It will look like crap:

    … but performance can be pretty devastating:

    A few people will of course shell out for a professionally made product, but it will be a few by definition, so while this is a great project technically, the market research could have been better if it was intended as a money making venture.

    • Komrad

      Got any links to how to build that?

      • bbmg

        this is the original thread:

        If you google “how to build a cloud BBMG” or “how to build a vortex BBMG” you will find plenty of tutorials online.

        On a basic level, you need a pressure source (in this case a coke bottle) connected to a trigger valve (in this case a garden hose gun but typically people use blowguns) connected to a BB chamber which is then connected to a barrel.

        The concept is very simple, similar to those lottery ball machines.

        You can see it filmed in high speed here:

        As you can see, the air flow into the chamber from the valve agitates the BBs, which then escape one by one through the barrel. Extremely high rates of fire (50 – 100 rounds per second) can be achieved depending on pressure, valve flow, projectile weight and barrel length.

  • A very interesting idea… Giving the plans away, and selling parts!

  • David/Sharpie

    I hope they tone down the fps a bit, back to -500 fps so we can own them in Canada.

    Yes this is an airgun that is illegal for me to own. In Canada, an airgun is considered a firearm if it shoots more than 500 fps, since this is, and is full auto, it’s considered prohibited.

    Just like a true machine gun……………………………..

  • Chrontius

    Heck with this thing; I want the GSMG they showed off initially. Mag fed, takes paintball CO2 tanks so you’re not burning through powerless or disposable 88-gram carts.

    I held off buying another airgun so I’d have money and a slot for that, and it’s vaporware.

    And now I’ve gone and bought the gun I held off on, just in time for everyone in town to stop selling the 88-gram “AirSource” cartridges it uses.

  • mike

    I wonder if they’ve looked at doing a kickstarter or something like that. Say they need, I dunno, $10,000 to go into production, set one of the pledge levels at like $25 for a copy of the plans, maybe $20 for a t-shirt, or a cap, $50 gets you plans and a tshirt, maybe $100 gets the valve, $200 gets the shell, $300 gets the valve and shell, and $500 gets the gun (or whatever amounts make sense, I’m just pulling them from air). It’s a great way to see who’s interested in paying, and if they don’t raise the $10,000 (or whatever amount they chose) then no one is out any money. And if they do raise it all by selling plans (and or parts), well then that is an answer, too.

  • charles

    i have a GMG, and let me tell you this thing just takes air rifles to another level. THE GMG IS FOR REAL AND NOT VAPORWARE!!! most people who shoot a pcp for the first time, never expect it to be so loud. BANG! it has to be about as loud as a .38, but i shoot in a valley so noise levels are hard to gauge without measuring equipment. You have to wear hearing protection, thats for sure. i can not shoot this thing in my urban backyard like i can a “normal” airgun. 600 fps is a bit conservative in my experience, but i don’t have a chrono to back it up. I even shoot 30g .22lr slugs from the american arms black powder pistol. Try that with a name brand air rifle. I had a buddy who recently passed away who was a SOT and had every subgun you can think off, so i have experience with class three firearms. so if the idea of loading the shells and having an air tank attached with a remote doesn’t bother you. the GMG gets you 100% the feeling of shooting a class three firearm without the red tape that goes along with it. I have an AR, semi of course, and i enjoy my GMG more. now all the guns that i want are pcp’s. once you get the associated equipment they are cheap to shoot and fun as hell. my next one will hopefully be a quackenbush bandit and i also have my sights on a caselman build. I love my GMG and yeah, it does cost a bit, but once you shoot one, you will “get it”.