Components of a firearm having a bolt with locking lugs improve shooting accuracy, due to increased coaxial alignment between the bolt, the cartridge, the receiver, and/or the barrel of a firearm. The receiver inner surface is shaped for lug-cleaning and for close tolerance/mating with the lugs only in the locked position and also with a non-threaded, axial surface of the barrel. Thus, the mating surfaces that are instrumental and/or that mainly control coaxial alignment of the receiver, bolt, and barrel are located between the lug stops and the threaded end of the receiver. The lugs may be axially curved or otherwise axially non-linear to tolerate dirt and other debris in a field environment.

Components of a firearm having a bolt with locking lugs improve shooting accuracy, due to increased coaxial alignment between the bolt, the cartridge, the receiver, and/or the barrel of a firearm. The receiver inner surface is shaped for lug-cleaning and for close tolerance/mating with the lugs only in the locked position and also with a non-threaded, axial surface of the barrel. Thus, the mating surfaces that are instrumental and/or that mainly control coaxial alignment of the receiver, bolt, and barrel are located between the lug stops and the threaded end of the receiver. The lugs may be axially curved or otherwise axially non-linear to tolerate dirt and other debris in a field environment.

A bolt action AR rifle can be prepared using a standard AR lower assembly and coupling it to a bolt action upper assembly. The bolt action upper assembly has a bolt action receiver containing a bolt. The method of forming a bolt action AR rifle can include: providing the bolt action upper receiver assembly; providing the standard AR lower AR receiver assembly having a pivot pin and takedown pin; inserting the pivot pin into the pivot pin receiver hole; pivoting the bolt action upper receiver assembly at the pivot pin until the takedown pin is aligned with the takedown pin receiver hole; and inserting the takedown pin into the takedown pin receiver hole.

A bolt action AR rifle can be prepared using a standard AR lower assembly and coupling it to a bolt action upper assembly. The bolt action upper assembly has a bolt action receiver containing a bolt. The method of forming a bolt action AR rifle can include: providing the bolt action upper receiver assembly; providing the standard AR lower AR receiver assembly having a pivot pin and takedown pin; inserting the pivot pin into the pivot pin receiver hole; pivoting the bolt action upper receiver assembly at the pivot pin until the takedown pin is aligned with the takedown pin receiver hole; and inserting the takedown pin into the takedown pin receiver hole.

A rife includes a receiver and a bolt body at least partially disposed in the receiver and including a body axis. The bolt body is discretely (1) rotatable about the body axis within the receiver and (2) axially slidable along the body axis. The rife also includes a bolt handle coupled to the bolt body so as to discretely (1) rotate with the bolt body about the body axis and (2) move with the bolt body along the body axis.

A rife includes a receiver and a bolt body at least partially disposed in the receiver and including a body axis. The bolt body is discretely (1) rotatable about the body axis within the receiver and (2) axially slidable along the body axis. The rife also includes a bolt handle coupled to the bolt body so as to discretely (1) rotate with the bolt body about the body axis and (2) move with the bolt body along the body axis.

A bolt for a bolt-action firearm in one embodiment is movably disposed in a receiver between forward closed breech and rearward open breech axial positions. The bolt includes an operating handle and plurality of bolt lugs arranged to selectively engage locking lugs in the firearm. The bolt is rotatable between locked and unlocked breech positions when in the closed breech position. The bolt body has a dimensionally reduced middle section with unique configuration adapted to allow the bolt to rotate when closed without interference from the magazine feed lips. Using this design, the bolt may include three bolt lugs in one embodiment for secure lockup and minimal angular rotation between the locked and unlocked breech positions. The bolt is usable with both single and double stack box type magazines with one of the bolt lugs operating to reliably strip cartridges from either type magazine.

A bolt for a bolt-action firearm in one embodiment is movably disposed in a receiver between forward closed breech and rearward open breech axial positions. The bolt includes an operating handle and plurality of bolt lugs arranged to selectively engage locking lugs in the firearm. The bolt is rotatable between locked and unlocked breech positions when in the closed breech position. The bolt body has a dimensionally reduced middle section with unique configuration adapted to allow the bolt to rotate when closed without interference from the magazine feed lips. Using this design, the bolt may include three bolt lugs in one embodiment for secure lockup and minimal angular rotation between the locked and unlocked breech positions. The bolt is usable with both single and double stack box type magazines with one of the bolt lugs operating to reliably strip cartridges from either type magazine.

Mid lock-up receivers have an elongated body, the body defining a passage, the body having a first rear portion and a second forward portion adjacent to and forward of the rear portion, the first rear portion defining a first passage segment having a first diameter and the second forward portion defining a second passage segment having a second diameter greater than the first diameter, a stop surface defined at a forward end of the first rear portion, an elongated sleeve defining a sleeve passage and received in the second passage segment, the sleeve having a rear-facing limit surface spaced apart from the stop surface, and the sleeve being compressively received in the body wherein the body is in tension about the sleeve, and the sleeve is compressed by the body. The sleeve may be thermally bonded to the body.

Mid lock-up receivers have an elongated body, the body defining a passage, the body having a first rear portion and a second forward portion adjacent to and forward of the rear portion, the first rear portion defining a first passage segment having a first diameter and the second forward portion defining a second passage segment having a second diameter greater than the first diameter, a stop surface defined at a forward end of the first rear portion, an elongated sleeve defining a sleeve passage and received in the second passage segment, the sleeve having a rear-facing limit surface spaced apart from the stop surface, and the sleeve being compressively received in the body wherein the body is in tension about the sleeve, and the sleeve is compressed by the body. The sleeve may be thermally bonded to the body.