Patent ID: 8375930

Claim:
A charging assembly for an air gun having a compression tube, the charging assembly comprising: a piston having a head and a skirt extending from the head along a longitudinal axis, wherein the piston is disposed within and supported by the compression tube and slideably moveable within the compression tube between a rearward position and a forward position; a power spring at least partially disposed within the skirt of the piston, wherein the power spring is moveable from a compressed position to an uncompressed position to move the piston from the rearward position into the forward position; wherein the power spring extends along the longitudinal axis and defines a hollow core; and a dampening system including: a rear guide tube disposed within the hollow core of the power spring and operable to radially support an inner diameter of the power spring when the power spring is disposed in the uncompressed position; and a sleeve disposed between an inner diameter of the skirt and an outer diameter of the power spring, and defining a bore, wherein the sleeve is coupled to and at least partially surrounds the rear guide tube with the rear guide tube and the power spring disposed within the bore, wherein the sleeve is operable to contact and radially support the outer diameter of the power spring when the power spring is disposed in the compressed position; wherein the sleeve and the rear guide tube cooperate to reduce a length of the power spring which is free to oscillate during the movement of the power spring from the compressed position into the uncompressed position to limit vibration of the power spring when fired.