An ambidextrous bolt catch having at least some of a bolt release lever having a bolt release projection, wherein the bolt release lever is rotatable between an engaged position and a disengaged position; and a bolt catch having a bolt catch recess, wherein at least a portion of the bolt release projection is received within at least a portion of the bolt catch recess, wherein the bolt catch is rotatable between an engaged position and a disengaged position, and wherein rotational movement of the bolt release lever produces rotational movement of the bolt catch, via interaction of at least a portion of the bolt release projection and at least a portion of the bolt catch recess.

Firearms with combined bolt catch and ejector have a bolt defining a bolt face configured to receive a case head of a cartridge, a bolt catch connected to a frame and movable between a first operational position in which bolt reciprocation forward from the rear position is enabled, and a second restraining position in which a portion of the bolt catch restrains the bolt in the rear position, and the bolt catch having an ejector surface portion positioned clear of the bolt face when the bolt catch is in the first operational position and in registration with a portion of the bolt face when the bolt catch is in the second restraining position such that a case head received by the bolt face strikes the ejector surface portion upon movement of the bolt from the forward to the rearward position when the bolt catch is in the second restraining position.

A lower receiver that may be right hand or left hand configurable is provided. The lower receiver includes a static ejector that can be easily configured for right hand or left hand positions within the same lower receiver and a magazine button assembly having a left magazine button and a right magazine button that are operatively coupled together so that either magazine button can be pushed to release the magazine. This allows the gun builder to use this one lower receiver to build a right or left handed rifle.

A lower receiver that may be right hand or left hand configurable is provided. The lower receiver includes a static ejector that can be easily configured for right hand or left hand positions within the same lower receiver and a magazine button assembly having a left magazine button and a right magazine button that are operatively coupled together so that either magazine button can be pushed to release the magazine. This allows the gun builder to use this one lower receiver to build a right or left handed rifle.

Ambidextrous bolts that allow a user to quickly and easily change the side of the firearm from which a spent casing is ejected by application of a simple switching mechanism that does not require disassembly of the firearm. Aspects of the disclosure also include debris shields for improving the longevity and reliability of extractors, firearms that are configured for ambidextrous operation, methods of using firearms, and methods of modifying firearms to incorporate ambidextrous functionality.

Ambidextrous bolts that allow a user to quickly and easily change the side of the firearm from which a spent casing is ejected by application of a simple switching mechanism that does not require disassembly of the firearm. Aspects of the disclosure also include debris shields for improving the longevity and reliability of extractors, firearms that are configured for ambidextrous operation, methods of using firearms, and methods of modifying firearms to incorporate ambidextrous functionality.

A device implementable on a firearm includes a monolithic upper receiver, comprising an upper receiver portion and a handguard portion, which is configured to accommodate non-proprietary barrel assemblies dimensioned according to United States military standard (mil-spec) barrel assembly dimensions and non-proprietary bolt carrier groups (BCGs) dimensioned according to mil-spec BCG dimensions. The device also includes a charging handle assembly configured to be coupled to an operating rod of a gas system of the firearm and forward of a BCG of the firearm. The device further includes a barrel locking system including a locking plate and a locking screw. When the locking screw is screwed into a threaded hole on the locking plate, the locking plate engages with a side of a barrel extension of the barrel assembly in a radial directions perpendicular to a longitudinal axis of the barrel assembly.

A device implementable on a firearm includes a monolithic upper receiver, comprising an upper receiver portion and a handguard portion, which is configured to accommodate non-proprietary barrel assemblies dimensioned according to United States military standard (mil-spec) barrel assembly dimensions and non-proprietary bolt carrier groups (BCGs) dimensioned according to mil-spec BCG dimensions. The device also includes a charging handle assembly configured to be coupled to an operating rod of a gas system of the firearm and forward of a BCG of the firearm. The device further includes a barrel locking system including a locking plate and a locking screw. When the locking screw is screwed into a threaded hole on the locking plate, the locking plate engages with a side of a barrel extension of the barrel assembly in a radial directions perpendicular to a longitudinal axis of the barrel assembly.

Implementations of charging handles may include a central shaft including a bolt engaging mechanism and a hand pull coupled to the central shaft. The hand pull may include a central block. The hand pull may also include a first wing having a first side and a second side, the first side opposite the second side. The hand pull may also include a second wing having a first side and a second side, the first side opposite the second side. The hand pull may also include a first opening extending into the second side of the first wing, a second opening extending into the second side of the second wing, a latch coupled to the second wing, the latch configured to couple within a receiver of a firearm, and a blade directly coupled to the latch, a cutting edge of the blade facing the central block.

Implementations of charging handles may include a central shaft including a bolt engaging mechanism and a hand pull coupled to the central shaft. The hand pull may include a central block. The hand pull may also include a first wing having a first side and a second side, the first side opposite the second side. The hand pull may also include a second wing having a first side and a second side, the first side opposite the second side. The hand pull may also include a first opening extending into the second side of the first wing, a second opening extending into the second side of the second wing, a latch coupled to the second wing, the latch configured to couple within a receiver of a firearm, and a blade directly coupled to the latch, a cutting edge of the blade facing the central block.