HK21

A product derived from G3, Heckler & Koch designed the 7.62 calibre machinegun HK21 in 1961. This MG fires from a closed bolt, operates on the roller-delayed blowback action mechanism of G3, chambered for 7.62x51mm NATO, able to fire at a rate of 800 rounds per minute cyclic, within a 1200 metres effective range coverage. The ambidextrous fire selector leaver allows HK21 to fire as semi-automatic on top of fully automatic firing, forearm of the weapon can mount a bipod for prone position/wall mounted firing. The belt feeding module is located beneath the receiver, which means HK21 can be modified/reconfigured to accept either box/drum magazines or to feed from munition belts. HK21 can be fed with 20-/30-round box magazines, 80-round drum magazine or lose/boxed ammo belts in lengths of 50 increments, HK21 can also make use of G3's 7.62 magazines. Close bolt firing meant the weapon have limited the maximum effective range and sustained firepower capabilities when compared to open bolt design MGs, however it does have a more accurate semi-automatic firing performance, to an extend they function relatively ideal as a squad automatic weapon. But HK21 did not enter full time service with the Bundeswehr, the main service MG contract during the cold war for West Germany was taken by Rheinmetal's MG3. With HK21 not being chosen as the main service MG, HK soon turn their development focus to export with the HK21 series of LMG, reconfigured, resized and rechambered variants such as HK11E, HK21E and HK23E were widely exported to many countries inside and outside of NATO. However the production of roller-delayed blowback MGs gradually slowed down with the trending interest in gas-operated MGs, HK ceased the production of HK21 lines of MG completely by early 2000, the new line of MG developed by HK would be the HK123 (MG4) family.