초록 ▼

An upper receiver assembly for a firearm having an upper receiver with an integral barrel nut, a handguard assembly and a barrel nut assembly with a barrel and lock nut is provided. The barrel is received by the upper receiver and is secured directly to the upper receiver using the lock nut. The upp

An upper receiver assembly for a firearm having an upper receiver with an integral barrel nut, a handguard assembly and a barrel nut assembly with a barrel and lock nut is provided. The barrel is received by the upper receiver and is secured directly to the upper receiver using the lock nut. The upper receiver also includes an integral handguard mounting member to which the handguard assembly may be directly attached. The upper receiver assembly allows the user to attach both the barrel and handguard assemblies directly to the upper receiver, independently of one another.

대표청구항 ▼

1. An upper receiver assembly for use with a firearm having a gas operating system, the upper receiver assembly comprising: a barrel assembly having a barrel, an annular flange about a back end of said barrel and a lock nut encircling a portion of the barrel;an upper receiver including a front end h

1. An upper receiver assembly for use with a firearm having a gas operating system, the upper receiver assembly comprising: a barrel assembly having a barrel, an annular flange about a back end of said barrel and a lock nut encircling a portion of the barrel;an upper receiver including a front end having a substantially cylindrical receiver extension extending therefrom, a forward end of said receiver extension having a substantially cylindrical opening with a threaded interior into which the back end of said barrel assembly is received, said front end having a bearing surface against which said annular flange of the barrel assembly rests, said threaded interior constructed to cooperate with threads on an outer surface of said lock nut so that said locknut, when threadedly secured inside the receiver extension, mounts said barrel assembly directly to said receiver extension of said upper receiver; andwherein said receiver extension is substantially shaped like an elongated cylinder with its top portion removed. 2. The receiver assembly of claim 1, further comprising a handguard assembly having a bottom segment and a separable top segment, a rear portion of said bottom segment being substantially cylindrical with a correspondingly cylindrical inner bore, a forward end of said receiver extension being received within said bottom segment inner bore and held therein to secure the handguard assembly directly to the receiver extension. 3. The receiver assembly of claim 2, further comprising a plurality of fasteners received within aligned openings in the receiver extension and openings in the bottom segment to removably secure said bottom segment of the handguard assembly to said receiver extension. 4. The receiver assembly of claim 1, further comprising a gas piston assembly and a placement above the receiver extension on a forward face of said upper receiver, said placement supporting and preventing rotation of a spring cup of said gas piston assembly. 5. The receiver assembly of claim 4, wherein said placement has a bore sized to receive a portion of an operating rod used with the gas piston assembly. 6. The receiver assembly of claim 1, wherein a forward face of said upper receiver includes an opening in communication with a channel that runs approximately parallel to the bore line of said barrel, said opening providing an entry for a portion of said gas operating system into said channel. 7. The receiver assembly of claim 6, wherein said opening in said receiver extension is machined to support a portion of said gas operating system, said opening having a forward end and a rearward end, said opening being wider at said forward end, gradually tapering down in diameter along its length towards said rearward end. 8. The receiver assembly of claim 1, further comprising a plurality of accessory mounting points which are removably secured about an exterior of a handguard assembly. 9. An upper receiver assembly for use with a gas operated firearm having a gas operating system, the upper receiver assembly comprising: a barrel having an annular flange about its back end;a lock nut fitted around a portion of said barrel;an upper receiver having a receiver extension on a forward end thereof and an interior circular channel wherein a portion of said barrel is received, said receiver extension being threaded about its interior and machined to be larger in diameter than said annular flange of said barrel and to threadedly receive said lock nut, a forward end of said interior circular channel having a bearing surface against which said annular flange of said barrel rests when the barrel and upper receiver are threadedly coupled with one another and secured by the lock nut;a handguard assembly including a top segment and a bottom segment, said bottom segment having a rearward end machined to receive and be secured to the receiver extension, said top segment being removably coupled to said bottom segment and restrained from movement by said bottom segment; andwherein said receiver extension is substantially shaped like an elongated cylinder with a top portion removed. 10. The upper receiver assembly of claim 9, further comprising a plurality of fasteners configured to removably secure said bottom portion of said handguard to said receiver extension. 11. The upper receiver assembly of claim 9, wherein said upper receiver further includes an opening located above and running parallel to said interior circular channel, said opening being configured to receive a portion of said gas operating system and rotationally restrain said portion of said gas operating system. 12. The upper receiver assembly of claim 11, wherein said opening is substantially wider at its forward end, gradually tapering down in diameter along its length towards its back end. 13. The upper receiver assembly of claim 9, further comprising a plurality of accessory mounting points which are removably secured about an exterior of said bottom segment of said handguard. 14. The receiver assembly of claim 9, wherein a rear portion of said handguard bottom segment being substantially cylindrical with a correspondingly cylindrical inner bore, said receiver extension being received within said bottom segment inner bore and secured thereto with fastening elements to mount the handguard assembly directly to the receiver extension. 15. An automatic firearm comprising: a buttstock and pistol grip;a lower receiver assembly;a barrel assembly having a barrel, an annular flange about a back end of said barrel and a lock nut encircling a portion of the barrel;a gas operating system;an upper receiver assembly, said upper receiver assembly including,an upper receiver with a receiver extension on a forward end thereof and an interior circular channel wherein a portion of said barrel is received, said receiver extension being threaded about its interior and machined to be larger in diameter than said annular flange of said barrel and to threadedly receive said lock nut, a forward end of said interior circular channel having a bearing surface against which said annular flange of said barrel rests when the barrel and upper receiver are threadedly coupled with one another and secured by the lock nut;a handguard assembly including a top segment and a bottom segment, said bottom segment having a rearward end machined to receive and be secured to the receiver extension, said top segment being removably coupled to said bottom segment and restrained from movement by said bottom segment; andwherein said receiver extension is substantially shaped like an elongated cylinder with its top portion removed. 16. The firearm of claim 15, wherein a forward face of said upper receiver includes an opening in communication with a channel that runs approximately parallel to a bore line of said barrel, said opening providing an entry for a portion of said gas operating system into said channel. 17. The firearm of claim 16, wherein said opening in said receiver extension is machined to support a portion of said gas operating system, said opening having a forward end and a rearward end, said opening being wider at said forward end, gradually tapering down in diameter along its length towards said rearward end. 18. The firearm of claim 15, further comprising a placement above the receiver extension on a forward face of said upper receiver, said placement supporting and preventing rotation of a spring cup of said gas operating system.