As the successor of the MG3, the HK121 opens a new era of universal belt fed 7.62 mm x 51 machine guns. Compared to others, the gas operated HK121 offers an intelligent and contemporary build standard, with numerous technical and ergonomic innovations. The mounting interface of the HK121 is compatible with MG3 mounts and tripods already in service. The universal HK121 can be used by dismounted infantry in the ground role, as well as for air defence or as a vehicle mounted/co axial machine gun.
HK121 A1 (Mounted). For FLW100, Puma turret configuration etc.
HK121 (Special Forces). With spade grip.
HK121 A2 (Infantry).
Heckler – Koch HK 121 universal / general purpose machine gun is a product of famous German arms-making company Heckler und Koch, designed as a possible replacement for ageing MG 3 general purpose machine guns, now in use by German military. This weapon was first announced in 2009, and in 2013 it was formally adopted by German army as MG5. MG5 is built on the basis of the previous HK machine gun, the 5.56mm MG 4, but with few parts being actually interchangeable due to different calibers and sizes.
Heckler – Koch HK 121 / MG5 machine gun is a gas operated weapon, firing from open bolt in automatic mode only. It has quick-detachable, air cooled barrel, with conventional rotary bolt locking. HK 121 gun is belt fed, using standard NATO disintegrating belts with M13 links, fed from clip-on 50-round containers or separate belt boxes. Gun is equipped with pistol grip and rifle-type trigger. Side-folding shoulder stock is made from polymer, and a small folding forend / forward grip is provided under the gas tube. Conventional folding bipod is attached below the gas block, and the gun can be installed on all mounts and tripods originally developed for MG 3 machine guns. In accordance with modern trends, it carries integral Picatinny rail at the top of the receiver, which can accept variety of day and night sights in addition to standard iron sights, which are provided with the gun.