Thanks to everyone who posted. With an estimate of 120-ish cubic inches, is that a tolerable size to go with a hand pump. I planned on stylizing one to attach to the cannon. If it is too large, should i consider co2 or just simply downsizing the chamber slightly? Going parts shopping tonight or wedn...

Hello, I'm new to the idea of coaxial/piston valves, though I do have previous experience with other pneumatic cannons (3 previous ball valves, various sizes), and some basic combustion cannons. I have read many of the posts and watched the tutorial on the building of the piston valve. I have the pl...