im using basic pvc pressure pipe with a very loose ball vavle,i didnt have the time to look for a modded valve but all in all she works good...
ive fired it at a bunch of towles i had hanging on the cloths line at 80 psi, with a marble.. it went straignt threw five layers of towleing!!! i cant believe it........ the barrel is the perfect size for a marble ,,im now throwing my combustion cannon to the shitter and embarking on my pneumatic cannon journey..
just an update there are photos on page 2 and 3 for the sprinkler valve setup and shortend chamber








