The Heckler & Koch MG4 5.56 is a germany-made full-auto lmg chambered in 5.56x45mm NATO, introduced in 2001. Primary use: military. Type: Machine Gun Action: Full-Auto Caliber: 5.56x45mm NATO Capacity: 100 Year introduced: 2001, Germany Weight: 256 oz Overall length: 47.5" Status: Active Intended use: military