Adjustable and Suppressible Gas Operating System for an Automatic Firearm

Abstract

A gas operating system for a firearm comprises a gas block defining a cylinder, a discharge gas vent coupled to the cylinder near a proximal end of the cylinder and a discharge gas inlet configured for pneumatic coupling with the barrel of a firearm near the proximal end of the cylinder. A piston in the cylinder is movable from a rest position distal of the discharge gas vent and the discharge gas inlet against the action of a return spring by discharge gas from a barrel of a firearm pneumatically coupled to the discharge gas inlet. A regulator is pneumatically coupled to the discharge gas vent to selectively control the flow of discharge gas from the discharge gas vent to modulate a volume of discharge gas advancing the piston. A diffuser may be provided pneumatically coupled to the regulator for diffusing any audible or visual report.

1 . A gas operating system for a firearm comprising:
 a gas block defining a cylinder, a discharge gas vent pneumatically coupled to the cylinder near a proximal end of the cylinder and a discharge gas inlet configured for pneumatic coupling with a barrel of a firearm near the proximal end of the cylinder;   a piston residing in the cylinder, the piston being movable from a rest position distal of the discharge gas vent and the discharge gas inlet against the action of a return spring by discharge gas from a barrel of a firearm introduced into the inlet upon discharge of a firearm having a barrel pneumatically coupled to the discharge gas inlet; and   a regulator pneumatically coupled to the discharge gas vent to selectively control a flow of discharge gas from the discharge gas vent to modulate a volume of discharge gas advancing the piston.   
   
   
       2 . The gas operating system of  claim 1  wherein the regulator comprises at least two orifices of different size which can be selectively pneumatically coupled to the discharge gas vent to control the flow of discharge gas from the discharge gas vent. 
   
   
       3 . The gas operating system of  claim 2  further comprising the regulator being attached to the gas block and rotatable relative to the gas block about a rotation axis, the at least two orifices being radially spaced from the axis, and the orifices being configured to be selectively pneumatically coupled to the gas discharge vent by rotation of the regulator about the axis. 
   
   
       4 . The gas operating system of  claim 3  further comprising the gas block defining a cylindrical cavity communicating with the discharge gas vent and the regulator comprising a cylindrical plug sized to be received in the cylindrical cavity along the rotation axis, the at least two orifices being defined in the cylindrical plug. 
   
   
       5 . The gas operating system of  claim 4  further comprising means removably attaching the regulator to the gas block. 
   
   
       6 . The gas operating system of  claim 5  wherein the removably attaching means comprises a pair of lugs extending radially from the cylindrical plug and annular channel in the cylindrical cavity configured to receive the lugs. 
   
   
       7 . The gas operating system of  claim 6  wherein the regulator further comprises a plurality of notches about the cylindrical plug and the gas block further comprises a spring loaded detent, the notches, the spring loaded detent and the orifices being configured for the spring loaded detent to extend into a notch with a select one of the at least two orifices pneumatically coupled to the gas discharge vent. 
   
   
       8 . The gas operating system of  claim 1  further comprising a diffuser pneumatically coupled to the discharge gas vent. 
   
   
       9 . A gas operating system for a firearm comprising:
 a gas block defining a cylinder, a discharge gas vent pneumatically coupled to the cylinder near a proximal end of the cylinder and a discharge gas inlet configured for pneumatic coupling with a barrel of a firearm near the proximal end of the cylinder;   a piston residing in the cylinder, the piston being movable from a rest position distal of the discharge gas vent and the discharge gas inlet against the action of a return spring by discharge gas from a barrel of a firearm introduced into the inlet upon discharge of a firearm having a barrel pneumatically coupled to the discharge gas inlet; and   a diffuser comprising an expansion chamber, the expansion chamber being pneumatically coupled to the discharge gas vent.   
   
   
       10 . The gas operating system of  claim 9  further comprising a regulator pneumatically coupled between the discharge gas vent and the diffuser to selectively control a flow of discharge gas from the discharge gas vent to modulate a volume of discharge gases advancing the piston. 
   
   
       11 . The gas operating system of  claim 10  wherein the regulator comprises at least two orifices of different size which can be selectively pneumatically coupled to the discharge gas vent to selectively control the flow of discharge gas from the discharge gas vent. 
   
   
       12 . The gas operating system of  claim 11  further comprising the regulator being attached to the gas block and rotatable relative to the gas block about a rotation axis, the at least two orifices being radially spaced from the rotation axis, and the orifices being configured to be selectively pneumatically coupled to the gas discharge vent by rotation of the regulator about the rotation axis. 
   
   
       13 . The gas operating system of  claim 12  further comprising the gas block defining a cylindrical cavity communicating with the discharge gas vent and the regulator comprising a cylindrical plug sized to be received in the cylindrical cavity along the rotation axis, the at least two orifices being defined in the cylindrical plug. 
   
   
       14 . The gas operating system of  claim 13  further comprising means removably attaching the regulator to the gas block. 
   
   
       15 . The gas operating system of  claim 14  wherein the removably attaching means comprises a pair of lugs extending radially from the cylindrical plug and annular channel in the cylindrical cavity configured to receive the lugs. 
   
   
       16 . The gas operating system of  claim 15  wherein the regulator further comprises a plurality of notches about the cylindrical plug and the gas block further comprises a spring loaded detent, the notches, the spring loaded detent and the orifices being configured for the spring loaded detent to extend into a notch with a select one of the at least two orifices pneumatically coupled to the gas discharge vent. 
   
   
       17 . The gas operating system of  claim 11  further comprising means removably attaching the suppressor to the regulator with the orifices pneumatically coupled to the expansion chamber. 
   
   
       18 . The gas operating system of  claim 9  further comprising a suppressor operatively associated with a muzzle of the barrel. 
   
   
       19 . The gas operating system of  claim 17  further comprising a cylindrical cavity defined in the regulator opposite the cylindrical plug, the diffuser comprising at least one radical baffle inserted in the cylindrical cavity of the regulator, the cylindrical cavity and the baffle cooperating to define the expansion chamber, and the means removably attaching the diffuser to the regulator comprises mating threads between the cylindrical cavity and the regulator. 
   
   
       20 . An automatic firearm comprising:
 a gas operating system comprising a gas block defining a cylinder and a piston within the cylinder, the cylinder being pneumatically coupled to a barrel of the automatic firearm, the piston being advanced in the cylinder against the action of the return spring by discharge gas released in the barrel upon firing the automatic firearm and the gas block further comprising a discharge gas vent pneumatically coupled to the cylinder;   a regulator pneumatically coupled to the discharge gas vent to selectively control a flow of discharge gas from the discharge gas vent to modulate a volume of discharge gas advancing the piston; and   a diffuser comprising an expansion chamber, the expansion chamber being pneumatically coupled to the regulator.