High Quality Content by WIKIPEDIA articles! The XM806 Lightweight .50 Caliber Machine Gun (LW50MG) is a .50 caliber heavy machine gun. The XM806 will weigh about 63 pounds (29 kg) less (49% lighter) and have 60% less recoil than the M2, and have a greater rate of fire than the failed previous attempt to replace the M2, the XM312. The XM806 does have a considerably slower rate of fire than the M2. The XM806 also has improvements to user safety and is easier to disassemble.