H&K HK121 Infantry.

Developed as the successor of the German Army’s MG3 general purpose machine gun. The mounting interface of the HK 121 is compatible with existing MG3 mounts and tripods already in service. The universal HK 121 can be used by dismounted infantry in the ground role, as well as for air defense or as a vehicle mounted/ coaxial machine gun. The HK121 shares several features with the 5.56 mm NATO HK MG4 light machine gun that was successfully adopted into German military service in 2005. The HK 121 machine gun is a gas-operated weapon, firing from an open bolt in automatic mode only. It has quick-detachable, air-cooled barrel, with a conventional rotary bolt locking function. The HK121 is belt fed, using standard NATO disintegrating belts with M13 links. The HK121 is fed from clip-on 50-round containers or separate belt boxes and is equipped with a pistol grip and rifle-type trigger. A variety of side-folding polymer buttstocks are available as well as a folding forend forward grip positioned under the gas tube. A conventional folding bipod is attached below the gas block, and the HK121 can an be installed on a wide variety of mounts and tripods. The HK121 is fitted with a Picatinny-type rail on the top of the receiver which can accept a variety of day and night sights in addition to standard mechanical sights. Currently the HK121 Infantry and Universal variants are available from HK-USA. Mounted (EBW) and Special Forces (S) variants are special order items. Cocking in all safety positions. Withstands barrel obstruction test to NATO-AC225/D14 standards (soft core and steel core ammunition DM111a1, DM151). Can be installed on all MG3 machine guns mounts and tripods. Full day and night fighting capability. NATO-STANAG 4694 mounting rails (compatible with MIL-STD-1913 Picatinny rails) for a variety of day and night sights or additional Accessories. Fixed, foldable and length-adjustable buttstock options. Mission related optional barrel lengths (quick change barrel with carrying handle). Can be quickly and easily reconfigured to a Mounted, Universal, Special Forces, or Infantry machine gun role without the use of tools. Robust and reliable even under extremely adverse environmental conditions. 3 position rate of fire adjustment. Special buffer reduces recoil forces and stabilizes the rate of fire. Ambidextrous safety/fire selector lever. Almost identical operation to the 5.56 mm HK MG4. Belt feed with loading indicator. HK121 for engagement of point or multiple targets (support/suppressive fire). Can be integrated into a remote controlled weapon station on military vehicles and used as primary vehicle machine gun or deployed as an anti-aircraft weapon. Integrated as a secondary or coaxial armament (e.g. armored vehicle turret configuration). Sustained fire support weapon for mobile infantry.