An action for a firearm uses a rotating barrel on which are mounted lugs and a cam follower. The barrel is positioned coaxially within a tube fixed to the frame of the firearm. A cam, engaged by the cam follower, is also fixed to the frame. A gas space is defined between the tube and the barrel by a thrust surface on the barrel and a reaction surface on the tube. A gas port connects the gas space with the barrel's bore. A slide overlies the tube and defines longitudinally oriented grooves which receive the lugs when the barrel is rotated by interaction between the cam and the cam follower to align the lugs and the grooves. Motion of the barrel is arrested by interaction between the cam and cam follower, and motion of the slide relative to the barrel is permitted when the lugs align and engage the grooves.

An action for a firearm uses a rotating barrel on which are mounted lugs and a cam follower. The barrel is positioned coaxially within a tube fixed to the frame of the firearm. A cam, engaged by the cam follower, is also fixed to the frame. A gas space is defined between the tube and the barrel by a thrust surface on the barrel and a reaction surface on the tube. A gas port connects the gas space with the barrel's bore. A slide overlies the tube and defines longitudinally oriented grooves which receive the lugs when the barrel is rotated by interaction between the cam and the cam follower to align the lugs and the grooves. Motion of the barrel is arrested by interaction between the cam and cam follower, and motion of the slide relative to the barrel is permitted when the lugs align and engage the grooves.

An assembly for directing propellant gas to an action of a firearm includes a barrel and a gas block. The barrel has a plurality of gas ports that communicate with the bore of the barrel. The barrel and the gas block define a passage that receives pressurized propellant gas from the bore by way of the barrel gas ports, and directs the propellant gas to a gas port of the gas block. The plurality of barrel gas ports and the passage act as a manifold in which the propellant gas is taken from multiple locations within the barrel, combined into a single flow, and directed into the gas block via the gas block gas port. The pressurized gas is then routed to an action of the firearm by way of a gas tube and a gas key.

An assembly for directing propellant gas to an action of a firearm includes a barrel and a gas block. The barrel has a plurality of gas ports that communicate with the bore of the barrel. The barrel and the gas block define a passage that receives pressurized propellant gas from the bore by way of the barrel gas ports, and directs the propellant gas to a gas port of the gas block. The plurality of barrel gas ports and the passage act as a manifold in which the propellant gas is taken from multiple locations within the barrel, combined into a single flow, and directed into the gas block via the gas block gas port. The pressurized gas is then routed to an action of the firearm by way of a gas tube and a gas key.

A firearm is described herein. The firearm comprises a receiver assembly adapted to receive a cartridge, a bolt assembly including a firing device operable to fire the cartridge, a barrel adapted to receive the projectile after the cartridge is fired, and a gas assembly including a gas tube. The receiver assembly includes an upper receiver portion, a lower receiver portion, and an upper receiver cover. The upper receiver portion defines a longitudinal axis, and an indexing slot operable to receive the gas tube. The upper receiver portion includes at least one integrated exterior track extending generally parallel to the longitudinal axis adapted to slidably couple with the upper receiver cover and a plurality of interior tracks extending generally parallel to the longitudinal axis adapted to slidably couple with the bolt assembly. The upper and lower receiver portions are pivotally connected to one another.

A firearm is described herein. The firearm comprises a receiver assembly adapted to receive a cartridge, a bolt assembly including a firing device operable to fire the cartridge, a barrel adapted to receive the projectile after the cartridge is fired, and a gas assembly including a gas tube. The receiver assembly includes an upper receiver portion, a lower receiver portion, and an upper receiver cover. The upper receiver portion defines a longitudinal axis, and an indexing slot operable to receive the gas tube. The upper receiver portion includes at least one integrated exterior track extending generally parallel to the longitudinal axis adapted to slidably couple with the upper receiver cover and a plurality of interior tracks extending generally parallel to the longitudinal axis adapted to slidably couple with the bolt assembly. The upper and lower receiver portions are pivotally connected to one another.

A rifle with a barrel firmly mounted in a framework, the barrel including a locking sleeve, a lock, a sliding block, and a gas-powered actuator. Advantageously quiet operation of the gas-powered actuator is accomplished when the actuator has an annular piston, which is movable on a plunger support, forming an expansion chamber, where the actuator acts on the sliding block via push rods and is pushed forward by reset springs, and the rifle further includes a gas borehole penetrating the walls of the barrel and the plunger support, and further where the plunger support includes an outlet channel in its front, upper range, which is fluidly separate from the expansion chamber when the annular piston is at rest, and is fluidly connected with the expansion chamber after a backward displacement of the annular piston.

A rifle with a barrel firmly mounted in a framework, the barrel including a locking sleeve, a lock, a sliding block, and a gas-powered actuator. Advantageously quiet operation of the gas-powered actuator is accomplished when the actuator has an annular piston, which is movable on a plunger support, forming an expansion chamber, where the actuator acts on the sliding block via push rods and is pushed forward by reset springs, and the rifle further includes a gas borehole penetrating the walls of the barrel and the plunger support, and further where the plunger support includes an outlet channel in its front, upper range, which is fluidly separate from the expansion chamber when the annular piston is at rest, and is fluidly connected with the expansion chamber after a backward displacement of the annular piston.

A gas piston assembly comprises a piston apparatus having a first end and a second end. A piston bonnet has a bonnet end wall with a bonnet aperture defined therethrough and a bonnet sidewall to receive the second end of the piston apparatus therein. A piston gap is between the second end of the piston apparatus and the bonnet end wall and communicates with the bonnet aperture. An adjustable gas regulator communicates with the bonnet aperture and selectively occludes the bonnet aperture in fully open, partially open and fully closed orientations. The bonnet end wall includes a threaded bore in communication with the bonnet aperture. The gas regulator includes a threaded shaft received within the threaded bore which translates to selectively occlude the bonnet aperture. The threaded shaft includes a head portion gripped by a user while a detent engages a recess on a bottom face of the head portion.

A gas piston assembly comprises a piston apparatus having a first end and a second end. A piston bonnet has a bonnet end wall with a bonnet aperture defined therethrough and a bonnet sidewall to receive the second end of the piston apparatus therein. A piston gap is between the second end of the piston apparatus and the bonnet end wall and communicates with the bonnet aperture. An adjustable gas regulator communicates with the bonnet aperture and selectively occludes the bonnet aperture in fully open, partially open and fully closed orientations. The bonnet end wall includes a threaded bore in communication with the bonnet aperture. The gas regulator includes a threaded shaft received within the threaded bore which translates to selectively occlude the bonnet aperture. The threaded shaft includes a head portion gripped by a user while a detent engages a recess on a bottom face of the head portion.