OK a air cannon how to make one quick and easy for about 50-75 USD you need
1. PVC pipe
2. Sprinkler valve
3. pneumatics tube
4. pneumatics fittings
take the sprinkler valve top off and drill a hole in the top of it in all the other holes plug up air tight. then let it dry for at lease 10 to 20 min. Make your cannon as big as you want but make sure you can fit it on the sprinkler valve. make sure one end has a cap on it and leave one end open for your barrel. drill a small hole in the end of the end cap and put a pneumatic hose fitting on it and connect you hose to the end of your gun. then screw you barrel and the end that you put the hose on to the valve then put a air trigger on the hose comming from the top of your valve and pump it up and you are good to go have fun and be safe my buddys put a hole in there wall
