Abstract: A trigger mechanism has a trigger block pivotably mounted on a trigger. The trigger block has a face surface that engages an actuation surface on a plunger which is movable along a line of action. The plunger has a stop surface engageable with a contact surface on the trigger. Pivoting of the trigger is prevented when the stop and contact surfaces are engaged. The plunger is spring biased to maintain the stop surface engaged with the contact surface. Pivoting of the trigger block moves the face surface against the actuation surface, which moves the plunger along its line of action. Motion of the plunger disengages the stop surface from the contact surface allowing the trigger to pivot and discharge the firearm.

Abstract: A rotary ammunition magazine for a rifle has a follower that is spring biased and rotates about an axis to move cartridges for feeding to the rifle's chamber. The follower has a rib and/or a projection on a surface facing the cartridges. The rib engages the last cartridge in a stack and directs the force from the follower in the direction of movement of the cartridges within the magazine. The projection engages the extractor groove in the last cartridge to prevent it from moving under inertial forces caused by recoil. The rib engages and prevents the last cartridge from moving down the follower. The projection and rib prevent bolt override malfunctions.

Abstract: A trigger mechanism for a firearm includes a sear which interacts with a trigger. The sear and trigger are held in contact by a sear block. The sear block has dogs which engage respective locking surfaces on the sear and trigger. Pivoting motion of the sear block disengages the dogs from the trigger and sear and allows the trigger to pivot and release the sear to discharge the firearm. When the dogs are engaged with the sear and trigger the resistance to inadvertent discharge due to inertial loads imposed on the mechanism when the firearm is dropped is increased.

Abstract: A rotary ammunition magazine for a rifle has a follower that is spring biased and rotates about an axis to move cartridges for feeding to the rifle's chamber. The follower has a rib and/or a projection on a surface facing the cartridges. The rib engages the last cartridge in a stack and directs the force from the follower in the direction of movement of the cartridges within the magazine. The projection engages the extractor groove in the last cartridge to prevent it from moving under inertial forces caused by recoil. The rib engages and prevents the last cartridge from moving down the follower. The projection and rib prevent bolt override malfunctions.

Abstract: A rotary ammunition magazine for a rifle has a follower that is spring biased and rotates about an axis to move cartridges for feeding to the rifle's chamber. The follower has a rib and/or a projection on a surface facing the cartridges. The rib engages the last cartridge in a stack and directs the force from the follower in the direction of movement of the cartridges within the magazine. The projection engages the extractor groove in the last cartridge to prevent it from moving under inertial forces caused by recoil. The rib engages and prevents the last cartridge from moving down the follower. The projection and rib prevent bolt override malfunctions.

Abstract: A magazine for a rifle having a fixed magazine has a cavity in an outwardly facing surface that receives a projecting boss immovable within the magazine well of the rifle. Once the magazine is inserted and the boss engages the cavity, the magazine is fixed and may not be removed from the rifle. The magazine is loaded by separating the upper receiver from the lower receiver and exposing the magazine opening, allowing it to receive rounds of ammunition.

Abstract: A trigger assembly has a sear with a stop surface engageable with a reciprocating component for holding the reciprocating component in a cocked configuration. A trigger is movable into and out of engagement with the sear to hold and release the reciprocating component. A drop pendulum has a trigger cam engageable with the trigger. A spring acts between the trigger and the drop pendulum to bias the trigger cam into engagement with the trigger. The drop pendulum also has a head cam follower engageable with the reciprocating component. Motion of the reciprocating component acting through the head cam follower and the trigger cam forces the trigger to return to a configuration of engagement between the trigger and the sear. Use of the drop pendulum improves the stability of trigger mechanisms and effectively inhibits accidental discharge of firearms when subjected to inertial forces which occur when the firearm is dropped.

Abstract: A trigger assembly has a sear with a stop surface engageable with a reciprocating component for holding the reciprocating component in a cocked configuration. A trigger is movable into and out of engagement with the sear to hold and release the reciprocating component. A drop pendulum has a trigger cam engageable with the trigger. A spring acts between the trigger and the drop pendulum to bias the trigger cam into engagement with the trigger. The drop pendulum also has a head cam follower engageable with the reciprocating component. Motion of the reciprocating component acting through the head cam follower and the trigger cam forces the trigger to return to a configuration of engagement between the trigger and the sear. Use of the drop pendulum improves the stability of trigger mechanisms and effectively inhibits accidental discharge of firearms when subjected to inertial forces which occur when the firearm is dropped.

Abstract: A fixed magazine for a rifle has a projecting boss within the magazine well that engages a cavity in the magazine. Once the magazine is inserted and the boss engages the cavity, the magazine is fixed and may not be removed from the rifle. The magazine is loaded by separating the upper receiver from the lower receiver and exposing the magazine opening, allowing it to receive rounds of ammunition.

Abstract: A fixed magazine for a rifle has a projecting boss that engages a cavity within the magazine well of the rifle. Once the magazine is inserted and the boss engages the cavity, the magazine is fixed and may not be removed from the rifle. The magazine is loaded by separating the upper receiver from the lower receiver and exposing the magazine opening, allowing it to receive rounds of ammunition.

Abstract: A fixed magazine for a rifle has a projecting boss within the magazine well that engages a cavity in the magazine. Once the magazine is inserted and the boss engages the cavity, the magazine is fixed and may not be removed from the rifle. The magazine is loaded by separating the upper receiver from the lower receiver and exposing the magazine opening, allowing it to receive rounds of ammunition.

Abstract: A catch is used to secure upper and lower receiver portions of a modern sporting rifle to one another. The catch may be mounted in either receiver portion and includes a shaft on which a body is mounted. The body has a hook and a cam follower positioned on opposite sides of the shaft. The cam follower engages a cam surface, which rotates the hook into engagement with a contact surface to secure the receiver portions to one another when they are pivoted into a closed configuration.

Abstract: A fixed magazine for a rifle has a projecting boss that engages a cavity within the magazine well of the rifle. Once the magazine is inserted and the boss engages the cavity, the magazine is fixed and may not be removed from the rifle. The magazine is loaded by separating the upper receiver from the lower receiver and exposing the magazine opening, allowing it to receive rounds of ammunition.

Abstract: An action lock for a Modern Sporting Rifle pump action firearm is pivotably mounted within the lower receiver of the rifle and has a stop surface that engages a contact surface on the bolt carrier when the bolt carrier is in battery. A cam on the hammer or the trigger engages a cam surface on the action lock when the hammer is released by a pull of the trigger. Cam action rotates the action lock out of engagement with the bolt carrier, unlocking it and allowing the fore end grip to be pumped to cycle the action and extract and eject the spent casing and strip and chamber a new round.