The M82 (also more recently known as the M107) is a heavy SASR (Special Application Scoped Rifle) developed by the American Barrett Firearms Company. It is used by many units and armies around the world, including the American Special Forces. It is also called the "Light Fifty" for its .50 caliber BMG (12.7 mm) chambering. The weapon is found in two variants — the original M82A1 (and A3) and the bullpup M82A2. The M82A2 is no longer manufactured, though XM500 can be seen as its successor, in that it also employs a bullpup configuration.