Heckler & Koch HK G3

Authored By: MilitaryFactory

At the end of World War 2, German engineers were working on perfecting a new breed of service rifle known as the "assault rifle". The assault rifle immediately antiquated the bolt-action service rifle as the standard-issue firearm of any modern army. The new weapon allowed use of a rifle-caliber cartridge in a more compact body with the capability of repeat, automatic fire at targets within short and medium ranges - ranges most often being encountered by infantry. The most famous early example of this type of weapon became the German wartime StG 44 (Sturmgewehr 44 or "Storm Rifle") - often cited as the "Father of Assault Rifles" - which led to a more refined and simpler prototype - the StG 45. Unfortunately for the Germans, the StG 45 only existed in prototype form before the end of the war in May of 1945 and perhaps as little as 30 units were produced.

Mauser Gerät 06(H) prototype. Image source :Springfield Armory National Historic Site

The StG 45 made use of the intermediate 7.92x33mm Kurz ("short") cartridge though, perhaps most importantly, it brought about the use of the "roller-delayed blowback" firing principle. This operation essentially involved two locking rollers situated to either side of the firing pin near the base of the cartridge, engaging the sides of the receiver during the firing action and delaying the movement of the bolt head - the barrel remaining fixed in place. The principle was adopted as a cost-effective alternative to a proposed gas-operated, roller-locked breech system originally intended for the StG 45. The end of the war stymied development of the StG 45 but German engineers, having relocated to Spain after the war, began perfecting the system under the government-sponsored Centro de Estudios Tecnicos de Materiales Especiales ("Technical Studio of Special Materials") otherwise known as CETME. The engineers managed to produce a more refined and reliable roller-delayed blowback system chambered for the 7.92mm cartridge and marketed it towards the West German Army for consideration as their new standard-issue service rifle. The West German Army favored the CETME idea but preferred a weapon utilizing the 7.62x51mm NATO standard cartridge instead. CETME engineers continued their work on the design and ultimately produced the CETME "Model 58" assault rifle/battle rifle firing a reduced-charge 7.62mm cartridge (to become the 7.62x51mm CETME).

After evaluation of competing systems, the West German Army selected the CETME design as their new standard-issue assault rifle. License-production of the weapon was obtained and the firm of Heckler & Koch revised the CETME system to accept the full-power 7.62x51mm NATO cartridge. The resulting design became the HK G3 series ("Gewehr 3") automatic rifle/battle rifle series which made use of sheet metal stampings in its construction dotted by furniture manufactured of plastic. The internal firing mechanism was a much more refined form of the original StG 45 roller-delayed blowback system and the overall construction of the rifle budget-friendly. The G3 shared much with the Spanish CETME but was, for all intents and purposes, its own evolution of the Stg 45 before it - a fairly straightforward, basic unassuming rifle formally categorized as a "Battle Rifle" due to its use of a full-power rifle cartridge. The HK G3 was introduced in 1959 and became the standard-issue service rifle of the West German Army. Some early HK G3s were, however, known to feature "CETME" stamped along their receivers, at least up until 1961.

The designator "G3" was used to simply mark the initial production models which were noted for their wooden shoulder stocks and flip over rear sights. The G3 followed much of the form and function of the preceding Spanish CETME Model B rifle marks and these were then followed into service by the HK GA1 which incorporated a retractable buttstock. The HK G3A2 mark were simply G3 service rifles with a standardized rotary rear sight installation. 

The HK G3A3 became the final production form of the G3 family line and its most definitive mark. The G3A3 utilized the rotary rear sight unit of the G3A2 models with a revised front sight and fixed plastic shoulder stock. Additionally, this version also saw its flash hider upgraded to a "prong" type. A bipod was optional for stabilized sustained fire. This version weighed in at 9lbs, 11oz with a 40 inch overall length and 17.7 inch barrel. Cyclic rate-of-fire was 550 rounds per minute with a muzzle velocity of 2,625 feet per second. The G3A3A1 incorporated a brass ejection port deflector and ambidextrous firing selector.