US Patent 7581537 Paintball gun with a pressure gauge device

A paintball gun with a pressure gauge device includes a rear cap, a pressure gauge, and a canopy. The rear cap has a first end and a second end. The rear cap has a compartment at the first end adapted to accommodate the pressure gauge. The second end of the rear cap has a piston block. The piston block has an air passage interconnecting with an air passage of the pressure gauge. The canopy is fixed to the rear cap which is then secured to a rear end of a barrel in the paintball gun. A triggering block is provided in the barrel. The triggering block engages with the rear cap. This design allows the user to read the air pressure within the paintball gun so that the user may apply air pressure to the paintball gun when necessary.