A HPA paintball tank pressurized to 3000 psi provides about 10 shots before it needs to be pumped up again. The cannon can also use 12 gram CO2 cartridges, although one 12g provides only a single shot! Without getting overly technical, the cannon’s main valve is a 1 inch ball valve that is rapidly opened by a single action pneumatic cylinder when the trigger switch (a 3 way 2 position valve) is depressed. The operating pressure is 250 psi, though everything is pressure rated at minimum for 3 times that for safety. It’s all steel construction, which is heavier and more expensive than PVC, but so much safer. It bothers me that a lot of home-built air cannons use PVC pipe for their pressure tanks when PVC can embrittle from UV exposure (like say, the sun). Also, PVC fragments don’t show up on an X-ray. Anyway, just wanted that safety stuff stated in case anyone else wants to try and build one. It is quite fun!
The barrel is constructed from 2 inch PVC, which is mounted to a sliding drawer bracket to allow for breech loading. I have a large spring to return the ball valve to the closed position after each shot to minimize lost air.
Feel free to ask any questions. Thanks for looking!
