Rifle modification

A modification for a M-16 type standard U.S. Army rifle having among its elements a barrel and a bolt with a bolt key secured thereto, comprising:

• (a) a forward cylinder connected to the front portion of the bore of the barrel wherein gas pressure from burning propellant powder is introduced, said cylinder having
• (1) adjustment means for varying the size of the bore of the cylinder whereby the force exerted by the propellant gases on the piston rod can be controlled, and
• (2) gas exhaust means;
• (b) a piston within the cylinder;
• (c) a rod connected to the piston extending rearwardly of the cylinder for transmitting force rearwardly to the bolt key;
• and
• (d) a buffer arrangement at the rearward portion of the piston rod and within the bolt key for absorbing the initial high impact force created by the gases in the forward cylinder which is transmitted rearwardly by the piston rod, said buffer system having a floating piston and a plurality of shock absorbing pads that are alternatingly different.