Hi guys, just for a daft laugh i made this air rifle, it plugs into my air compreessor "120 psi"and pumps up the cylnder, i ram some plastic bag down the mussel as wadding, then pop in a half inch ball bearing,i have another valve near the barrel "a sliding one" with when opened propels the steel ball and a great rate of knots! i.e it will punch a hole in a forty gallon drum at 18 metres, i reuse the wadding and the balls! it also takes aa batteries and glass marbels, regards Bob