The
Heckler and Koch G3, to give it its full name, was one of the most popular post-war
battle rifles amongst the
Western powers and those who fell within their spheres of influence. America had the
M16, Britain and the
Commonwealth had the
FN FAL, whilst most others opted for the
G3. Like the FAL it was chambered for the
7.62x51 mm round and was therefore something of an
anachronism throughout its long life.
The rifle was based heavily on the Spanish CETME, a rifle which was in turn created by ex-Mauser engineers who had left Germany at the end of WW2. The CETME itself was based on Mauser's prototype Sturmgewehr 45, a device which would have replaced the MP43 in the army of Nazi Germany if Nazi Germany had continued beyond 1945.
The G3 was spun off from the CETME between 1955 and 1959, at which point it became the German army's standard weapon. The rifle was cheaper and easier to produce than the FN FAL and sold well abroad, both as a commercial product and as a licence - many other countries, including Brazil, Chile, Sweden and Turkey, made their own subtly-differing variants. Along with the MP5 the G3 kept Heckler and Koch afloat for some time, until the protracted gestation of the G11 and German reunification did for them.
As with the FAL the G3 is powerful and accurate, but suffers from being chambered for a heavy round; as the rifle uses a blowback system for cycling, recoil is heavier, and with the 7.62mm cartridge full-automatic fire is impractical. The G3 is still used by some units of the German army and as a training and reserve weapon, but outside a few nations in Africa, Asia and Eastern Europe it has largely been replaced by 5.56x45mm weapons. The Germany Army now uses the Heckler and Koch G36. Highly modified versions are still popular in the form of the PSG-1 sniper rifle and the MP5 submachine gun.
The civilian version is called the Heckler and Koch HK91 and is semi-automatic only.