Rifle

Abstract

A rifle with an upper receiver and a barrel attached to the upper receiver and including a bolt carrier, and operating, buffer, and cooling systems. The operating system includes a cylinder and a piston coupled to receive propelling gases from the barrel. As the piston moves between retracted and extended positions the bolt carrier is moved between closed and open positions. The bolt carrier includes a weight movable within a guide frame between rearward and forward limits. The buffer system includes a compression spring in a tube attached to the upper receiver in abutting engagement with the bolt carrier. A partially fluid filled cylinder is attached to a coil of the spring and includes a piston and shaft. The piston is formed so that fluid in the cylinder restricts movement in one direction and allows free movement in a second direction.

Having fully described the invention in such clear and concise terms as to enable those skilled in the art to understand and practice the same, the invention claimed is: 
     
         1 . A handguard comprising:
 a tubular portion, where the tubular portion is configured to slide over a barrel and slide over a barrel nut; and   a rail attached to the tubular portion, where an alignment portion rotationally aligns the rail to a receiver, where the tubular portion is configured to have an inner surface, where the inner surface exerts a force on the barrel nut when a force is exerted on the tubular portion.   
     
     
         2 . The handguard according to  claim 1 , where the alignment portion is part of the receiver. 
     
     
         3 . The handguard according to  claim 1 , where the alignment portion is configured to be inserted into a portion of the handguard and where the alignment portion is configured to be inserted into part of the receiver. 
     
     
         4 . A rifle comprising:
 the handguard of  claim 1 ;   a barrel; and   an upper receiver.   
     
     
         5 . The rifle according to  claim 4 , further comprising:
 a barrel nut.   
     
     
         6 . The rifle according to  claim 5 , where the handguard and the upper receiver are formed from a single unitary piece of metal. 
     
     
         7 . The rifle according to  claim 6 , further comprising:
 a receiver rail.   
     
     
         8 . The rifle according to  claim 7 , further comprising:
 an extending portion, where the extending portion is configured to rotationally align the handguard rail with the upper receiver.   
     
     
         9 . The rifle according to  claim 8 , where the handguard is configured to slide over at least a portion of the operating system. 
     
     
         10 . The rifle according to  claim 9 , where the operating system includes a piston and a push rod system. 
     
     
         11 . The rifle according to  claim 10 , where the piston and push rod system includes a piston and a push rod, where the piston and a push rod are separate components. 
     
     
         12 . The rifle according to  claim 11 , where the piston is configured to exert force on the push rod.