The XM8 LMG is a variant of the XM8 baseline carbine; it has a heavy 20 inch (508mm) barrel for sustained fire and increased accuracy, integrated folding bipod, built-in 4X Reflex Sight, and a 100 round Beta-C magazine. This variant of the baseline carbine is meant to be used as a light machine gun rather than an ordinary assault rifle such as its long barrel (LB) XM8 counterpart or the M16 assault rifle.