Introduction: AIR CANNON

 Here is an air cannon I made with on old air compressor tank and some other junk I had lying around. The only cost to me was the ball valve that cost about $50.
 I may need to move the pressure gauge to another available port that is not on the fill stem, I'm not sure if I am getting a true read.
The entire gun is made from steel and brass except for the barrel that is after the ball valve is PVC to reduce some weight.
 I am also still working on an elevator to move the muzzle up and down for more accurate shots.I thought of using a screw/scissor jack but I think It may be too bulky and slow. I am open to suggestions if anyone wants to contribute....



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    12 Discussions

    Oh yeah by the way, everything is metal except the barrel after the ball valve, it is PVC. I used it to bring the weight down some.

    I'm not sure but i will tell you this... The tank is 120 psi max, I put 50 lbs in it and shot a tennis ball straight up in the air and I followed it until it was out of sight. I'm not exactly sure how high it went but I'm guessing about 300-400 feet perhaps?? I have yet to fill it to compacity since I live in the city and don't want to have the neighbors on me. But am anticipating a max shot!! How do I test the muzzle energy?

    1 reply

    Probably a little too late to reply considering you're four years older than then but here's a formula to help you find the speed and then you can use that to find the amount of joules it would produce:

    Speed = sq root ( (2 x length of pipe x PSI x Pi x r2) / mass)


    2 years ago

    I can think of all kinds of things to shoot out of that thing


    2 years ago

    Have you tried different ammo


    3 years ago

    Look sweet to me nice job!

    Did you weld the attachment on the end for the valve and barrel? I'm working on a bait caster and your design looks better than my PVC model.

    This is awesome. Have a tee in the barrel and use round ammo that will slide freely in the pipe. If t he tee has a small curve, have it curve toward the valve. Drop in lots of ammo into a pipe connected to the arm of the tee. Make sure the tee is right after the thread adapter. You may end up shooting several projectiles at once! Use a clean-out adapter and a plug at the end of the clip. It really works.

    Like you, I had a spare air tank. I had a Sch40 1.5" nipple welded in one end, brass valve, and a length of PVC for a barrel. There's a bit too much wobble in the barrel to my liking, so I'm turning it 'round, coming over the top from the back with a couple of 90' then supporting the barrel with a vertical support tac welded to the tank. Barrel elevation (you might like to use this) is a bracket tacked on the rear allowing a pipe to slide up and down vertically and a set screw/knob to hold it where placed.

    Starting on the bait bullets next! No more tempting the great whites seen around here lately when wading out to shoulder depth in the surf to get a better cast. :-)

    How about a length of threaded rod attached to the base and tank with a swivel point. If placed at the rear of the tank, plus a nut with a sleeve between it and the tank, moving the nut up and down the rod would adjust the trajectory. The nut could be made easy to turn by welding three or four metal rods to the flats on the nut to form a star of sorts.

    Upgrade. Affix a pointer on the sleeve aimed at a protractor on a stationary upright and it would be possible to dial in a target with a few rounds or consistently hit a target if the distance to target is known. I'm sure there's some one with artillery experience would have even better ideas.