A 5.56×45mm NATO Assault Rifle developed from the late 1990s to early 2000s, designed by Heckler & Koch. Firing from a closed rotary bolt, it shares design and engineering with their G36 Rifle.
The materials used to build the XM8 are almost entirely composites, with the notable exception of the cold-hammer-forged steel barrel. Preliminary tests in desert and arctic conditions have shown the XM8 to be a rugged weapon, though some complaints arose.
While the XM8 fell out of favor with the US military, Heckler & Koch sought to market the rifle globally.
The XM8 is sometimes nicknamed as the "fish gun" due to its peculiar shape.