Tactical firearm having heat shielding properties and improved gas energized cartridge feeding

Abstract

A tactical firearm has an upper receiver defining a handguard mounting surface oriented in substantially normal relation with the bore of a rifle barrel and defining handguard mounting flanges that project radially from the upper receiver. A handguard is provided with like radiating handguard mounting flanges and is releasably secured to the upper receiver by fasteners. A barrel extends through the handguard and is secured by a barrel retainer to the upper receiver in a manner achieving clearance and thermal isolation of the handguard from the barrel and barrel retainer.

I claim: 
     
         1 . A tactical firearm, comprising:
 a receiver member defining a first mounting flange and having a first rail mounting surface;   a handguard member defining a second mounting flange being secured in face to face relation with said first mounting flange; and   flange fastener members securing said first and second mounting flanges in releasable fixed relation with one another.   
     
     
         2 . The tactical firearm of  claim 1 , comprising:
 said receiver member defining a first rail mounting surface and said handguard member defining a second rail mounting surface being disposed in co-planar relation with said first rail mounting surface;   a one-piece elongate sight mounting rail extending substantially along the combined length of said receiver member and said handguard member and defining a mounting surface having face to face relation with said first and second rail mounting surfaces, said one-piece elongate sight mounting rail having a cross-sectional mount geometry for receiving clamp type sight mount devices in releasable clamped relation therewith; and   rail fastener members securing said one-piece elongate sight mounting rail to said receiver and said handguard.   
     
     
         3 . The tactical firearm of  claim 2 , comprising:
 said receiver having a rear end portion and a front end portion;   said handguard having a rear end portion and a front end portion; and   said one-piece elongate sight mounting rail having a rear end located at said rear portion of said receiver and a front end located at said front portion of said handguard and being vertically tapered from a predetermined dimension at said rear end to a dimension less than said predetermined dimension at said front end thereof.   
     
     
         4 . The tactical firearm of  claim 1 , comprising:
 a barrel member extending through said handguard member and being mounted to said receiver member;   a barrel retainer nut being threaded to said receiver member and securing said barrel member in oriented and substantially immovable relation with said receiver member; and   said handguard defining an inner surface disposed in spaced relation with said barrel member and said barrel nut and being thermally isolated from metal conducted transfer of heat from said barrel member and said barrel retainer nut to said handguard.   
     
     
         5 . The tactical firearm of  claim 1 , comprising:
 a one-piece elongate sight mounting rail being mounted to said receiver and said handguard and having a length substantially equal to the combined length of said receiver and said handguard; and   said one-piece elongate sight mounting rail being tapered along a major portion of the length thereof and defining a predetermined angle of cant for location of sighting devices at any selected position along the length thereof.   
     
     
         6 . The tactical firearm of  claim 5 , comprising:
 said one-piece elongate sight mounting rail defining a rear portion located at a rear portion of said receiver and a front portion located at a front portion of said handguard having a greater vertical thickness at said rear portion as compared with the vertical thickness at said front portion thereof.   
     
     
         7 . The tactical firearm of  claim 5 , comprising:
 said one-piece elongate sight mounting rail defining a single mechanical sight mount located at said rear portion thereof, said single mechanical sight mount having an elevation permitting manual sighting of said firearm when optical sighting devices have been removed from said one-piece elongate sight mounting rail.   
     
     
         8 . The tactical firearm of  claim 5 , comprising:
 said one-piece elongate sight mounting rail having a plurality of equally spaced lands and sight positioning grooves located substantially along the length thereof; and   said one-piece elongate sight mounting rail defining a single mechanical sight mount structure being located at the rear portion of said one-piece elongate sight mounting rail and having a sight orienting surface and mechanical sight positioning groove for attachment of a mechanical sighting device thereon.   
     
     
         9 . The tactical firearm of  claim 1 , comprising:
 said receiver member having a bolt chamber located therein;   a bolt carrier having reciprocating movement within said bolt chamber and having a bolt member located therein;   a buttstock being mounted to said receiver member and having a buffer housing therein defining a buffer stop;   a spring urged buffer member being moveable within said buffer housing and having reciprocating movement limited by said buffer stop; and   said bolt carrier having a portion thereof located within said buffer housing and in contact with said buffer member and having guided relation with said buffer stop and preventing tilting of said bolt carrier during rearward movement thereof.   
     
     
         10 . The tactical firearm of  claim 1 , comprising:
 said receiver member having a bolt chamber located therein;   a bolt carrier having reciprocating cartridge autoloading movement within said bolt chamber and having a bolt member located therein, said bolt carrier and bolt member being moved rearwardly within said bolt chamber by cartridge gas pressure resulting from firing of said tactical firearm;   a buffer housing having a bolt carrier guide member;   a spring urged buffer member having rearward movement within said buffer housing responsive to rearward movement of said bolt carrier and having forward movement within said buffer housing by said spring; and   said bolt carrier having a portion thereof in guided relation with said carrier guide member and being guided during rearward and forward reciprocating movement of said bolt carrier and bolt.   
     
     
         11 . The tactical firearm of  claim 1 , comprising:
 said receiver member being defined by an upper receiver defining a bolt chamber and a lower receiver having a buttstock and defining a buffer housing;   a spring urged buffer member being moveable within said buffer chamber; and   a bolt carrier having a bolt member therein and having a rear end portion thereof in constant engagement with said buffer member and in anti-tilt guided relation with said buffer housing, upon rearward movement of said bolt carrier responsive to cartridge firing said bolt carrier causing rearward cushioning movement of said spring urged buffer member and being guided by said buffer housing to prevent tilting thereof during both rearward cartridge firing movement and forward spring urged movement.   
     
     
         12 . A tactical firearm, comprising:
 a receiver member defining a first mounting flange and having a first rail mounting surface;   a handguard member defining a second mounting flange and having a second rail mounting surface disposed in co-planar relation with said first rail mounting surface, said first and second mounting flanges being mounted in face to face relation and defining a firearm unit of rigid and structurally enhanced character;   flange fastener members securing said first and second mounting flanges in releasable fixed relation with one another;   a one-piece elongate sight mounting rail extending substantially along the combined length of said receiver member and said handguard member and defining a substantially planar mounting surface having face to face relation with said first and second rail mounting surfaces, said one-piece elongate sight mounting rail having a cross-sectional mount geometry for receiving clamp type sight mount devices in releasable clamped relation therewith; and   rail fastener members securing said one-piece elongate sight mounting rail in fixed relation with said receiver and said handguard and further enhancing the rigidity and structurally enhanced character of said firearm unit.   
     
     
         13 . The tactical firearm of  claim 12 , comprising:
 said receiver having a rear end portion and a front end portion;   said handguard having a rear end portion and a front end portion; and   said one-piece elongate sight mounting rail having a rear end located at said rear portion of said receiver and a front end located at said front portion of said handguard and being vertically tapered from a predetermined dimension at said rear end to a dimension less than said predetermined dimension at said front end thereof.   
     
     
         14 . The tactical firearm of  claim 12 , comprising:
 a barrel member extending through and in free-floating relation within said handguard member and having cartridge receiving relation with said receiver member;   a barrel retainer nut being threaded to said receiver member and securing a rear end portion of said barrel member in oriented and substantially immovable relation with said receiver member; and   said handguard defining an inner surface disposed in spaced relation with said barrel member and said barrel nut and being thermally isolated from metal conducted transfer of heat from said barrel member and said barrel retainer nut to said handguard.   
     
     
         15 . The tactical firearm of  claim 12 , comprising:
 a one-piece elongate sight mounting rail being mounted to said receiver and said handguard and having a length substantially equal to the combined length of said receiver and said handguard; and   said one-piece elongate sight mounting rail defining a rear portion located at a rear portion of said receiver and a front portion located at a front portion of said handguard having a greater vertical thickness at said rear portion as compared with the vertical thickness at said front portion thereof and being tapered along the length thereof and defining a predetermined angle of cant for location of sighting devices at any selected position along the length thereof   
     
     
         16 . The tactical firearm of  claim 15 , comprising:
 said one-piece elongate sight mounting rail defining a single mechanical sight mount located at said rear portion thereof, said single mechanical sight mount having an elevation permitting manual sighting of said firearm when optical sighting devices have been removed from said one-piece elongate sight mounting rail;   a plurality of equally spaced lands and sight positioning grooves being located substantially along the length of said one-piece elongate sight mounting rail having; and   a single mechanical sight mount structure being located at the rear portion of said one-piece elongate sight mounting rail and having a sight orienting surface and mechanical sight positioning groove for attachment of a mechanical sighting device thereon.   
     
     
         17 . The tactical firearm of  claim 12 , comprising:
 said receiver member having a bolt chamber located therein;   a bolt carrier having reciprocating movement within said bolt chamber and having a bolt member located therein;   a buttstock being mounted to said receiver member and having a buffer housing therein defining a buffer stop;   a spring urged buffer member being moveable within said buffer housing and having reciprocating movement limited by said buffer stop; and   said bolt carrier having a portion thereof located within said buffer housing and in contact with said buffer member and having guided relation with said buffer stop and preventing tilting of said bolt carrier during rearward movement thereof.   
     
     
         18 . The tactical firearm of  claim 12 , comprising:
 said receiver member having a bolt chamber located therein;   a bolt carrier having reciprocating autoloading movement within said bolt chamber and having a bolt member located therein, said bolt carrier and bolt member being moved rearwardly within said bolt chamber by cartridge gas pressure resulting from firing of said tactical firearm;   a buffer housing having a bolt carrier guide member;   a spring urged buffer member having rearward movement within said buffer housing responsive to rearward movement of said bolt carrier and having forward movement within said buffer housing by said spring; and   said bolt carrier having a portion thereof in guided relation with said carrier guide member and being guided during rearward and forward reciprocating movement of said bolt carrier and bolt.   
     
     
         19 . The tactical firearm of  claim 12 , comprising:
 said receiver member being defined by an upper receiver defining a bolt chamber and a lower receiver having a buttstock and defining a buffer housing;   a spring urged, buffer member being moveable within said buffer chamber; and   a bolt carrier having a bolt member therein and having a rear end portion thereof in constant engagement with said buffer member and in anti-tilt guided relation with said buffer housing, upon rearward movement of said bolt carrier responsive to cartridge firing said bolt carrier causing rearward cushioning movement of said spring urged buffer member and being guided by said buffer housing to prevent tilting thereof during both rearward cartridge firing movement and forward spring urged movement.