HK G3

Heckler & Koch G3
The G3A4 (top) and G3A3 (bottom)
Type	Battle rifle
Place of origin	West Germany
Service history
In service	1959–present
Used by	See Users
Wars	See Conflicts
Production history
Designer	CETME Mauser Heckler & Koch
Designed	1956
Manufacturer	Heckler & Koch (original) Rheinmetall MIC SEDENA Defense Industries Organization Fábrica de Braço de Prata Bofors Carl Gustaf Husqvarna Vapenfabriks Aktiebolag Elliniki Viomihania Oplon Kongsberg Våpenfabrikk MAS Military Industry Corporation MKEK Pakistan Ordnance Factories Royal Ordnance Bangladesh Ordnance Factories
Produced	1958–present
No. built	7,000,000
Variants	See Variants
Specifications
Weight	4.1 kg (9.04 lb) (G3A3) 4.7 kg (10 lb) (G3A4) 5.54 kg (12.2 lb) with optic (G3SG/1) 4.1 kg (9.0 lb) (G3K)
Length	1,025 mm (40.4 in) (G3A3) 1,025 mm (40.4 in) stock extended / 840 mm (33.1 in) stock collapsed (G3A4) 1,025 mm (40.4 in) (G3SG/1) 895 mm (35.2 in) stock extended / 711 mm (28.0 in) stock collapsed (G3K)
Barrel length	450 mm (17.7 in) 315 mm (12.4 in) (G3K)
Cartridge	7.62×51mm NATO
Action	Roller-delayed blowback
Rate of fire	500–600 rounds/min
Muzzle velocity	800 m/s (2,625 ft/s)
Effective firing range	500 metres (550 yd), 100–400 m sight adjustments
Feed system	20-round detachable box 30-round detachable box and 50-round drum magazine
Sights	Rear: rotary diopter; front: hooded post

The G3 is a 7.62×51mm NATO battle rifle developed in 1956 by the German armament manufacturer Heckler & Koch GmbH (H&K) in collaboration with the Spanish state-owned design and development agency CETME (Centro de Estudios Técnicos de Materiales Especiales).

The origin of this rifle can be traced back to the final years of World War II when Mauser engineers at the Light Weapon Development Group (Abteilung 37) at Oberndorf am Neckar designed the MKb Gerät 06 (Maschinenkarabiner Gerät 06 or "machine carbine device 06") prototype assault rifle chambered for the intermediate 7.92×33mm Kurz cartridge, first with the Gerät 06 model using a roller-locked short recoil mechanism originally adapted from the MG 42 machine gun but with a fixed barrel and conventional gas-actuated piston rod. It was realized that with careful attention to the mechanical ratios, the gas system could be omitted. The resultant weapon, the Gerät 06H (the "H" suffix is an abbreviation for halbverriegelt or "half-locked") was assigned the designation StG 45(M) (Sturmgewehr 45(M) or assault rifle) but was not produced in any significant numbers and the war ended before the first production rifles were completed.

The German technicians involved in developing the StG 45(M) were taken to work in France at CEAM (Centre d'Etudes et d'Armement de Mulhouse). The StG 45(M) mechanism was modified by Ludwig Vorgrimler and Theodor Löffler at the Mulhouse facility between 1946 and 1949. Three versions were made, chambered in .30 Carbine, 7.92×33 mm Kurz as well as the experimental 7.65×35 mm French short cartridge developed by Cartoucherie de Valence in 1948. A 7.5×38 mm cartridge using a partial aluminium bullet was abandoned in 1947. Löffler's design, designated the Carabine Mitrailleuse Modèle 1950, was retained for trials among 12 different prototypes designed by CEAM, MAC, and MAS. Engaged in the Indochina War and being the secondNATO contributor, France canceled the adoption of these new weapons for financial reasons.