The invention relates to a part called base rubber (1) and/or butt rear rubber which is developed to be used in butts of the bullpup rifles. Said base rubber (1) has a feature that is adjustable in different sizes according to the demand of the user.

A detachable monolithic cheek riser for a firearm stock or brace comprises a top portion having an inside surface that is shaped to match the shape of the top of the stock or brace, and includes side portions that extend downward from the top such that each side portion rests on opposite sides of the stock or brace. At the bottom of the sides of the cheek riser there are retention tabs that extend inward, toward the opposite side, and which are configured to fit into recesses on the sides of the stock or brace when the check riser is attached to the stock or brace. No tool is required to install or remove the cheek riser, as a result.

A detachable monolithic cheek riser for a firearm stock or brace comprises a top portion having an inside surface that is shaped to match the shape of the top of the stock or brace, and includes side portions that extend downward from the top such that each side portion rests on opposite sides of the stock or brace. At the bottom of the sides of the cheek riser there are retention tabs that extend inward, toward the opposite side, and which are configured to fit into recesses on the sides of the stock or brace when the check riser is attached to the stock or brace. No tool is required to install or remove the cheek riser, as a result.

An adjustable cheek rest for a rifle stock having a butt with opposed major faces and an uppermost crest line separating opposed first and second stock upper surfaces each angling in opposite directions angularly offset away from a vertical direction associated with the uppermost crest line. The cheek rest comprises a base having a base side portion configured to overlay a selected major face of the stock; the base having a base upper portion connected to the base side portion and configured to extend over the uppermost crest line to the opposed upper surface away from the selected major face; the base upper portion having a first base upper portion surface configured to overlay the first stock upper surface, and a second base upper portion surface configured to overlay the second stock upper surface; and a cheek piece connected to the base and movable with respect to the base between a lower position and an upper position, and a plurality of intermediate positions.

An adjustable cheek rest for a rifle stock having a butt with opposed major faces and an uppermost crest line separating opposed first and second stock upper surfaces each angling in opposite directions angularly offset away from a vertical direction associated with the uppermost crest line. The cheek rest comprises a base having a base side portion configured to overlay a selected major face of the stock; the base having a base upper portion connected to the base side portion and configured to extend over the uppermost crest line to the opposed upper surface away from the selected major face; the base upper portion having a first base upper portion surface configured to overlay the first stock upper surface, and a second base upper portion surface configured to overlay the second stock upper surface; and a cheek piece connected to the base and movable with respect to the base between a lower position and an upper position, and a plurality of intermediate positions.

A recoil absorber for a firearm including a housing, a stock carrier assembly, a primary spring, and a damper cartridge assembly. The damper cartridge assembly includes a high pressure chamber, a low pressure chamber, and a piston. The piston includes a first piston orifice, a second piston orifice, a second spring, and a poppet which includes a poppet orifice. The second spring applies a biasing force on the poppet. Fluid may flow from the high pressure chamber through the poppet orifice and through the first piston orifice into the low pressure chamber when the pressure of the fluid in the high pressure chamber is between a first pressure and a second pressure. When the pressure increases above the second pressure, the poppet compresses the second spring to self-regulate the pressure in the high pressure chamber.

A recoil absorber for a firearm including a housing, a stock carrier assembly, a primary spring, and a damper cartridge assembly. The damper cartridge assembly includes a high pressure chamber, a low pressure chamber, and a piston. The piston includes a first piston orifice, a second piston orifice, a second spring, and a poppet which includes a poppet orifice. The second spring applies a biasing force on the poppet. Fluid may flow from the high pressure chamber through the poppet orifice and through the first piston orifice into the low pressure chamber when the pressure of the fluid in the high pressure chamber is between a first pressure and a second pressure. When the pressure increases above the second pressure, the poppet compresses the second spring to self-regulate the pressure in the high pressure chamber.

A firearm stock extension assembly enables a stock to be collapsed when a firearm is not in active use, and extended from a collapsed configuration directly to the user's preferred stock length. This is accomplished without requiring the user to actuate a lever to release a detent mechanism and without the need for hand tools to adjust the length of the stock. The firearm stock extension assembly includes an insert that defines at least one insert aperture. When properly placed, the insert aperture of the insert lines up with a corresponding extension aperture on the stock. Other than the corresponding extension aperture exposed by the insert aperture, all other extension apertures are concealed by the solid portions of the insert.

A firearm stock extension assembly enables a stock to be collapsed when a firearm is not in active use, and extended from a collapsed configuration directly to the user's preferred stock length. This is accomplished without requiring the user to actuate a lever to release a detent mechanism and without the need for hand tools to adjust the length of the stock. The firearm stock extension assembly includes an insert that defines at least one insert aperture. When properly placed, the insert aperture of the insert lines up with a corresponding extension aperture on the stock. Other than the corresponding extension aperture exposed by the insert aperture, all other extension apertures are concealed by the solid portions of the insert.

A stock assembly for a firearm, the stock assembly comprising a buffer catch comprising a movable buffer catch body; a receiver extension comprising a buffer tube; the buffer tube comprising a buffer tube body and a tubular passage within the buffer tube body; the buffer tube body comprising a buffer catch receptacle extending through a wall of the buffer tube body extending along a longitudinal axis of the buffer tube; the buffer catch receptacle configured to receive the buffer catch body therein; the buffer catch body configured to move within the buffer catch receptacle from a home position to a depressed position; and, in the depressed position, the buffer catch body blocks at least a portion of the tubular passage of the buffer tube.