you should have at least put the butane can next to a flame lol awesome cannon

If I'm not mistaken a 12 gram co2 cartridge runs at 1200 psi its a nice design but i would be careful when calculating your chamber volume to get it just right.

nice gun, long gun tho also you should use a 180 and fold the chamber back on itself bet it packs a hell of a punch tho

lol i wouldn't want to say eye out around this thing very clean nice job