In addition to some combustion ones, Ive gotta jumbo pneumatic cannon. Its tank is a 9 foot length of 4" pvc, with a 1.5" barrel contained inside it. It empties that tank- fast- with a custom made piston diaphram valve. I did a muzzle velocity test with the pendulum method and at 60 psi, it shoots a potato at 450 mph. It can shoot em right through 1.5" plywood or split a 2 by 8.
Its pretty fun...but a certain tree in my yard that is missing alot of bark disagrees
