# US 8,783,160 B2 · Firearm with gas operating system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,160 B2 - Document ID: US8783160B2 - Status: Granted - Kind: B2 - Application number: 13/964,664 - Filed: 2013-08-12 - Published: 2014-03-20 - Granted: 2014-07-22 - Earliest claimed: 2006-02-09 - Assignees: Colt's Manufacturing Company Inc. - Applicants: Colt Defense LLC - Inventors: Paul Hochstrate; Laurance Robbins; Arthur F. Daigle - Web page: https://patentgrep.com/patent/US8783160B2 ## CPC - F41A 5/18: gas-operated - F41A 3/66: Breech housings or frames; Receivers - F41A 5/26: Arrangements or systems for bleeding the gas from the barrel (F41A5/20 - F41A5/24 take precedence) - F41A 11/02: Modular concepts, e.g. weapon-family concepts - F41C 23/16: Forestocks; Handgrips; Hand guards (pump-action guns F41C7/02) - F41G 1/02: Foresights - F41G 11/003: {Mountings with a dove tail element, e.g. "Picatinny rail systems"} - Y10T 29/49826: Assembling or joining - F41A: FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE - F41C: SMALLARMS, e.g. PISTOLS, RIFLES (functional features or details common to both smallarms and ordnance, mountings therefor F41A; projecting missiles without use of explosive or combustible propellant charge F41B); ACCESSORIES THEREFOR - F41G: WEAPON SIGHTS; AIMING (optical aspects thereof G02B) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An indirect gas operating system for a semi-automatic or automatic rifle is provided, the indirect gas operating system having: a gas block secured to the rifle; a barrel secured to the rifle; a bolt carrier slidably received within a receiver of the rifle; a means for moving the bolt carrier within the receiver using gases discharged into a bore of the barrel of the rifle, wherein the means for moving is removably secured to the gas block such that the means for moving can be removed from the rifle through a forward end of the gas block without removing the gas block from the rifle; and an externally threaded barrel nut for securing the barrel to the receiver. ## Claims ### Claim 1 An indirect gas operating system for a semi-automatic or automatic rifle, the indirect gas operating system comprising: a gas block secured to the rifle; a barrel secured to the rifle; a bolt carrier slidably received within a receiver of the rifle; a means for moving the bolt carrier within the receiver using gases discharged into a bore of the barrel of the rifle, wherein the means for moving is removably secured to the gas block such that the means for moving can be removed from the rifle through a forward end of the gas block without removing the gas block from the rifle; and an externally threaded barrel nut for securing the barrel to the receiver. ### Claim 2 (depends on 1) The indirect gas operating system as in claim 1, wherein the receiver further comprises an integral hand guard portion and a removable hand guard portion. ### Claim 3 (depends on 2) The indirect gas operating system as in claim 2, wherein the removable hand guard portion when removed provides access to the barrel nut that secures the barrel to the receiver. ### Claim 4 (depends on 3) The indirect gas operating system as in claim 3, wherein the receiver is an upper receiver and the upper receiver is removably secured to a lower receiver of rifle. ### Claim 5 (depends on 4) The indirect gas operating system as in claim 4, wherein the barrel and barrel nut can be removed from the rifle without removing the means for moving the bolt carrier within the receiver of the rifle. ### Claim 6 (depends on 5) The indirect gas operating system as in claim 5, wherein the external thread of the barrel nut interfacing with threads of the receiver when the barrel nut secures the barrel to the receiver. ### Claim 7 (depends on 6) The indirect gas operating system as in claim 6, wherein a barrel extension is located between the barrel and the barrel nut. ### Claim 8 (depends on 7) A rifle having the indirect gas operating system of claim 7. ### Claim 9 (depends on 1) The indirect gas operating system as in claim 1, wherein the means for moving further comprises a means for varying a gas pressure provided from the bore of the barrel towards the bolt carrier. ### Claim 10 (depends on 9) The indirect gas operating system as in claim 9, wherein the receiver further comprises an integral hand guard portion and a removable hand guard portion. ### Claim 11 (depends on 10) A rifle having the indirect gas operating system of claim 10. ### Claim 12 (depends on 1) A rifle having the indirect gas operating system of claim 1. ### Claim 13 A semi-automatic or automatic rifle having an indirect gas operating system, comprising: a gas block fluid coupled to a bore of a barrel of the rifle; a bolt carrier slidably received within a receiver of the rifle; a sleeve removably secured to a forward end of the gas block of the rifle; a piston slidably received within the gas block, wherein the gas block and the sleeve fluidly couple the piston to the bore of the rifle; wherein an increase in pressure in the bore of the rifle causes the piston to move away from the sleeve; wherein the sleeve and the piston are each capable of being removed from the rifle through the forward end of the gas block; and wherein the receiver has an integral hand guard portion and a removable hand guard portion and wherein the removable hand guard portion when removed from the receiver provides access to a barrel nut that secures the barrel to the receiver. ### Claim 14 (depends on 13) The semi-automatic or automatic rifle as in claim 13, wherein the receiver is an upper receiver and the upper receiver is removably secured to a lower receiver of rifle. ### Claim 15 (depends on 14) The semi-automatic or automatic rifle as in claim 14, wherein the barrel and barrel nut can be removed from the receiver without removing sleeve and piston from the receiver of the rifle and wherein the barrel nut is externally threaded for interfacing with threads of the receiver and wherein a barrel extension is located between the barrel and the barrel nut. ### Claim 16 A method of fluidly coupling a barrel of a semi-automatic or automatic rifle to a bolt carrier of the rifle, comprising: providing a means for moving a bolt carrier within a receiver of the rifle using gases discharged into a bore of a barrel of the rifle, wherein the means for moving is removably secured to a gas block of the rifle such that the means for moving can be removed from the rifle through a forward end of the gas block without removing the gas block from the rifle; and removably securing a removable hand guard portion to an integral hand guard portion of the receiver of the rifle, wherein the removable hand guard when removed provides access to a barrel nut that secures the barrel to the rifle. ### Claim 17 (depends on 16) The method as in claim 16, wherein the barrel and barrel nut can be removed from the rifle without removing the means for moving the bolt carrier within the receiver of the rifle. ### Claim 18 (depends on 17) The method as in claim 17, wherein the barrel nut is externally threaded for interfacing with threads of the receiver. ### Claim 19 (depends on 18) The method as in claim 18, wherein a barrel extension is located between the barrel and the barrel nut.