Rail Extension Device

Abstract

A rail extension device for a belt fed machine gun includes a first and a second section of rail for mounting auxiliary devices, the second section being rotatable relative to the first section to prevent a collision between an auxiliary device mounted on the second section of rail and the weapon when a feed tray cover is opened to reload.

1 . A rail extension device configured to be coupled to a firearm, said device comprising:
 a base plate having a top surface defining a first rail interface, said base plate having a first end configured to be rotatably coupled to a frame portion of said firearm and a second end configured to be coupled to a feed tray cover of said firearm, said base plate being movable about a first axis between a first base plate position and a second base plate position, said first axis substantially perpendicular with a barrel of said firearm; and   a rail member having a top surface defining a second rail interface, said rail member rotatably coupled to said base plate and movable about a second axis between a first rail member position and a second rail member position, said second axis substantially parallel with said barrel of said firearm;   wherein said top surface of said base plate and said top surface of said rail member form a substantially planar rail interface when said rail member and said base plate are in said first rail member and said first base plate positions, respectively; and   wherein said top surface of said rail member is substantially orthogonal to said top surface of said base plate when said rail member is in said second rail member position.   
     
     
         2 . A rail extension device configured to be coupled to a portion of an existing mounting rail defined on a frame portion of a firearm, said rail extension device comprising:
 a base plate having a top surface defining a first rail interface, said base plate having a first end configured to be rotatably coupled to a frame portion of said firearm and a second end configured to be coupled to an existing mounting rail of a frame portion of said firearm, said base plate being movable about a first axis between a first base plate position and a second base plate position, said first axis substantially orthogonal with a barrel of said firearm; and   a rail member having a top surface defining a second rail interface, said rail member rotatably coupled to said base plate and movable about a second axis between a first rail member position and a second rail member position, said second axis substantially parallel with said barrel of said firearm;   wherein said top surface of said base plate and said top surface of said rail member form a substantially planar rail interface when said rail member and said base plate are in said first rail member and said first base plate positions, respectively; and   wherein said top surface of said rail member is substantially orthogonal to said top surface of said base plate when said rail member is in said second rail member position.   
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . A rail extension device configured to be coupled to a rail of a firearm, comprising:
 a first rail member having an underside surface having a profile configured to cooperate with the rail of the firearm; a first boss having a first opening extending therethrough, one or more fasteners for removably coupling the first rail member to the rail of the firearm; a first upper surface defining a first rail interface for securing an auxiliary device thereto;   a second rail member having a second upper surface defining a second rail interface for securing an auxiliary device thereto and a second boss having a second opening extending therethrough; and   a pin extending through the first opening in the first boss and the second opening in the second boss to allow the second rail member to rotate relative to the first rail member about an axis parallel with a longitudinal axis of the first rail member.   
     
     
         6 . The rail extension device of  claim 5 , wherein the second rail member is rotatable from a first position in which the second upper surface is parallel to the first upper surface and a second position in which the second upper surface is generally perpendicular to the first upper surface. 
     
     
         7 . The rail extension device of  claim 6 , further comprising a spring to bias the second rail member towards the second position. 
     
     
         8 . The rail extension device of  claim 5 , wherein a longitudinal axis of the pin extends along an axis parallel to an axis of a barrel of the firearm when the rail extension member is mounted to the firearm. 
     
     
         9 . The rail extension device of  claim 7 , wherein the spring is a torsion spring and is secured in place by a pin. 
     
     
         10 . The rail extension device of  claim 6 , further comprising a latch for securing the second rail member in the first position. 
     
     
         11 . The rail extension device of  claim 10 , further comprising a release trigger, the release trigger configured to unlatch the latch and allow the second rail member to rotate from the first position to the second position when the release trigger is actuated. 
     
     
         12 . The rail extension device of  claim 11 , wherein the release trigger is coupled to the second rail member and when the rail extension device is mounted to the firearm the release trigger is actuated by rotation of the rail extension device from a first position to a second position. 
     
     
         13 . The rail extension device of  claim 6 , wherein the second upper surface is generally coplanar with the first upper surface when the second rail member is in the first position. 
     
     
         14 . The rail extension device of  claim 5 , wherein the first upper surface and the second upper surface have a profile consistent with MIL-STD-1913. 
     
     
         15 . The rail extension device of  claim 5 , further comprising a rear latch assembly securable to an end of the first rail member spaced from the second rail member, the rear latch assembly comprises a rotatable knob to disengage latches that hold the rail extension device in a first position thereby allowing the rail extension device to rotate into a second position. 
     
     
         16 . The rail extension device of  claim 15 , wherein rotation of the rail extension device from the first position to the second position causes a release trigger to be actuated which causes the second rail member to become unlatched to the first rail member. 
     
     
         17 . The rail extension device of  claim 5 , wherein the first rail member is configured to accept a day optic and the second rail member is configured to accept a night vision device, the day optic being aligned with night vision device when the second rail member is in the first position.