US Patent 7237544 Pneumatic paintball gun and components

An electro-pneumatic paintball gun preferably comprises a bolt assembly and a firing valve assembly that can be readily removed from the paintball gun. A bolt assembly preferably comprises a bolt sleeve. The bolt assembly is preferably removed by turning the bolt sleeve a predetermined rotational distance and then retracting the bolt assembly from a rearward opening in the paintball gun. The firing assembly preferably comprises a pneumatic piston rod and cylinder and a firing valve. A firing mass is preferably arranged on a rearward end of the piston rod. The forward end of the piston rod preferably engages the firing valve. The firing mass can include a groove for receiving a bolt linkage from the bolt assembly.