The G3 is a 7.62mm battle rifle developed in the 1950s by the German armament manufacturer Heckler & Koch in collaboration with the Spanish state-owned design and development agency CETME.
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 at Oberndorf am Neckar designed the MKb Gerat 06 prototype assault riflechambered for the intermediate 7.92x33mm Kurz cartridge, first with the Gerat 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 Gerat 06H (the "H" suffix is an abbreviation for halbverriegelt or "half-locked") was assigned the designation StG 45(M) but was not produced in any significant numbers and the war ended before the first production rifles were completed.
The CEAM Modele 1950, a French effort to put the StG 45(M) concept into mass production. Chambered in .30 Carbine.
The German technicians involved in developin the StG 45(M) were taken to work in France at CEAM. The StG 45M mechanism was modified by Ludwig Vorgrimler and Theodor Loffler at the Mulhouse facility betweeen 1946 and 1949. Three versions were made, chambered in .30 Carbine, 7.92x33mm as well as the experimental 7.65x35mm French short cartridge developed by Cartoucherie de Valence in 1948. A 7.5x38mm cartridge using a partial aluminum bullet was abandoned in 1947. Loffler's design, designated the Carabine Miltralleuse Modele 1950, was retained for trials among 12 different prototypes designed by CEAM, MAC, and MAS. engaged in the Indochina War and being the second NATO contributor, France canceled the adoption of these new weapons for financial reasons.
In 1950, Vorgrimler moved to Spain where he created the LV-50 rifle chambered for the Kurz cartridge and later, the proprietary7.92x40mm CETME M53 round. At this point, the rifle was renamed the Modelo 2. The Modelo 2 drew the attention of the West German Border Guards, who sought to re-equip the newly formed national defense forces. Not willing to accept a cartridge outside of the NATO specification, the Germans asked CETME to develop a 7.62x51mm version of the rifle. The resulting CETME Model A was chambered for the 7.62x51mm CETME cartridge which was identical in chamber dimensions but had a reduced-power load compared to the 7.62mm NATO round. Further development of the rifle with input from H&K produced the CETME Model B which received several modifications, including the ability to fire from a closed bolt, in both semi-automatic and automatic firing modes, a new perforated sheet metal handguard (the folding bipod had been the forgrip in previous models), improved ergonomics and a slightly longer barrel with a 22 mm rifle grenade launcher guide. In 1958, this rifle was accepted into service with the Spanish Army as the Modelo 58, using the 7.62x51mm CETME round.
In 1956, the Bundesgrenzschutz canceled their planned procurement of the CETME rifles, adopting the Belgian-made FN FAL (G1) instead. However, the newly formed West German Army (Bundeswehr) now showed interest and soon purchased a number of CETME rifles (7.62x51mm NATO chambering) for further testing. The CETME, known as the Automatisches Gewehr G3 according to German nomenclature, competed successfully against the Swiss SIG SG 510 (G2) and the American AR-10 (G4) to replace the previously favored G1 rifle. In Jan. 1959, the Bundeswehr oficially adopted the CETME proposal. The West German government wanted the G3 rifle to be produced under license in Germany; purchase of the G1 had previoulsy fallen through over FN's refusal to grant such a license. In the case of the G3, the Dutch firm Nederlandse Wapen en Munitiefabriek (NWM) held production and sales right to the CETME design outside of Spain. To acquire production rights, the West German Government offered NWM contracts to supply the German Air Force (Luftwaffe) with 20mm ammunition. Production of the G3 was then assigned to Rheinmetall and H&K. The latter company already had ties to CETME, and had worked to further optimize the CETME rifle for use with the full-power 7.62x51mm NATO cartridge (as opposed to the downloaded CETME variant). In 1969, Rheinmetall gave up production rights to the G3 in exchange for H&K's promise not to bid on MG-3 production. Later in 1977, the West German government ceded ownership of G3 production and sales rights exclusively to H&K.
Initial production G3 rifles differed substantially from more recent models; early rifles featured closed-type mechanical flip-up sights (with two apertures), a lightweight folding bipod, a stamped sheet steel handguard, a wooden buttstock (in fixed stock models) or a telescopic metal stock. The weapon was modernized during its service life, resulting in the most recent production models, the G3A3 (with fixed polymer stock) and the G3A4 (telescoping metal stock). The rifle proved successful in the export market, being adopted by the armed forces of over 40 countries.
Design details[]
A schematic of the G3 roller-delayed blowback mechanism.
The G3A3 (A4) is a selective-fire automatic weapon that employs a roller-delayed blowback operating system. The two-piece bolt assembly consists of a breech (bolt head) and bolt carrier. The bolt is held in battery by two sliding cylindrical rollers that engage locking recesses in the barrel extension (properly called a "trunnion"). The breech is opened when both rollers are compressed inward against camming surfaces driven by the rearward pressure of the expanding gases upon the bolt head. As the rollers move inward, recoil energy is transferred to the locking piece and bolt carrier which begin to withdraw while the bolt head slowly moves rearward in relation to the bolt carrier. As the bolt carrier clears the rollers, pressure in the bore drops to a safe level, the bolt head is caught by the bolt carrier and moves to the rear as one unit, continuing the operating cycle. The bolt also features an anti-bounce mechanism that prevents the bolt from bouncing off the barrel's breech surface. The spring-powered claw extractor is also contained inside the bolt while the lever ejector is located inside the trigger housing (actuated by the recoiling bolt).
The H&K G3A4 (top) and G3A3 cutaway (bottom).
The rifle is hammer fired and has a trigger mechanism with a 3-position fire selector switch that is also the manual safety toggle that secures the weapon from accidentally discharging. The weapon can be fitted with an optional 4-position safety/fire selector group illustrated with pictograms with an ambidextrious selector lever. The additional, fourth selector setting enables a 3-round burst mode of fire.
A Bundeswehr G3 fitted with a FERO-Z51 night vision optic.
The firearm was equipped with iron sights that consist of a rotary rear drum and hooded front post. The rear sight, mechanically adjustable for both windage and elevation, has an open notch used to fire up to 100 meters and three apetures used for 200, 300, and 400 meters. The receiver housing has recesses that work with HK clamp adaptors used to mount day or night optics.
The rifled barrel (contains 4 right-hand grooves with a 305mm twist rate) terminates with a slotted flash suppressor which can also be used to attach a bayonet or serve as an adaptor for launching rifle grenades. From the G3A3 the barrel had polygonal rifling. The barrel chamber is fluted, which assists in the initial extraction of a spent cartridge casing (since the breech is opened under very high barrel pressure).
Disassembled G3A3 rifle. Note: modular design.
The G3A3 (A4) uses either steel (260 g) or aluminum (140 g) double-stacked straight box magazines, or 50 round drum magazine. Original H&K drums are rare and command high prices, a reproduction is available at much less cost from Allied Armament. H&K developed a prototype plastic disposable magazine in the early 1960s, but it was not adopted as aluminum magazines were just as light and proved more durable, as well as easier to produce.
The G3 is a modular weapons system. Its buttstock, fore-stock and pistol-grip/fire control assembly may be changed at will in a variety of configurations (listed below). For example: by simply pushing push pins the fixed buttstock cam be removed and replaced with a telescoping butt-stock.
Variants[]
Apart from the G3A3 and G3A4 H&K built: the G3A3ZF (essentially a G3A3 with a Hensoldt 4x24 optical sight), the accurized G3SG/1 rifle (hand-selected G3A3s, equipped with an improved trigger, Zeiss telescopic sight with a variable 1.5-6x magnification and a cheek riser) and the G3K carbine which uses an HK33 handguard and shorter barrel, that is too short for use with the bayonet or rifle grenades.
G3A3
The G3 served as a basis for many other weapons, among them: the PSG1 and MSG90 precision rifles, the HK11 and HK21 family of light machine guns.
German sniper with G3A3ZF-DMR in Afghanistan.
G3: Original model based on the CETME Modelo B
G3A1: G3 with a single position, collapsible stock. This design was chosen after earlier experimentation with a ventrally-folded stock. Excesssive recoil caused the latter to be dropped from consideration.
G3A2: G3 with rotating drum rear sight.
G3A3: The most well known version. Drum sights, a fixed plastic buttstock, and a plastic handguard that does not contact the barrel. The handguard came in a slim, ventilated version and a wide version. The latter allows for the attachment of a bipod.
G3A3A1: This is a version of the G3A3 with an ambidextrious trigger group and brass deflector. This is an official German Army designation, not an HK factory one.
G3A4: The G3A4 uses drum sights an a single position, collapsible stock. This rifle could also be issued with a scope with the nomenclature G3A4ZF. The ZF stands for Zielfernrohr or "Telescope".
G3A4A1: This is a variant of the G3A4 with an ambidextrious trigger group and brass deflector. This is an official German Army designation, not an HK factory one.
G3KA4: Smallest of the line, it is a Karabiner, or carbine version of the G3. It features drum sights, a retractable stock, and a 315mm barrel.
G3KA4A1: Variant of the G3KA4 with an ambidextrious trigger group and brass deflector. This is an official German Army designation, not an HK factory one.
G3A5: HK assigned model number for the HK-made Danish version of the G3A3. It differs in that it has a silent bolt-closure device. In Danish service it is known as the Gv M/66. The Gv M/66 was originally intended for use with optics as a designated marksman rifle, while the rest of the squad were issued M1 Garands.
G3A6: HK assigned model number for the Iranian-made version of the G3A3.
G3A7: HK assigned model number for the Turkish-made version of the G3A3.
HSG1: HK assigned model number for the Luxembourg-made version of the G3A3.
Other military variants and derivatives[]
A Norwegian soldier takes cover behind a wall from simulated fire during a NATO excercise. The soldier is using the license-built AG3 model.
Gv M/75: Variant leased from the German Bundeswehr/German government by the Danish government to replace the aging M1 Garands. Originally manufactured by either Rheinmetall or HK for the German Bundeswehr. The Gv M/75 rifles are basically G3's with the old style straight cocking tube as opposed to the later FS (Freischwinger) variant. Semi-automatic normally, though could be converted to fully automatic fire by changing the safety lever. This is done without tools.
AG-3: Norwegian G3A5 variant produced by Kongsburg Vapenfabrikk. A total of 253,497 units were produced for the Norwegian Armed Forces from 1967 to 1974. The Norwegian AG-3 differs from the original G3; it has a buttstock that is approximately 2 cm longer, the bolt carrier has a serrated thumb groove to aid in silent bolt closure, it features an all metal cocking handle and a different bayonet mount. On Apr. 11, 2007, it was announced that the AG-3 would be replaced by the H&K HK416, in all military branches except for certain groups of the Home Guard.
AG-3F1: An AG-3 with a retractable stock as on a G3A4. Produced by Kongsburg Vapenfabrikk. A retractable stock was required by certain groups of soldiers within the Norwegian Armed Forces, primarily vehicle crews with limited space inside, particularly where a quick disembarkment from such a vehicle is required. All versions of the AG-3 have the ability to attach a 40 mm HK79 grenade launcher.
AG-3F2: An improvement of the AG-3F1, featuring Picatinny rails on the receiver as well as the foregrip.
Ak 4: Swedish-made version of the G3A3, with a buttstock that is approx. 2 cm longer, the bolt carrier has a serrated thumb groove to aid in silent bolt closure and fitted with a heavy buffer for higher number of round fired before failure. The rifles were manufactured from 1965 to 1985. Also produced with a Hensoldt 4x24 telescopic sight mounted via an HK claw mount, known as the Ak 4OR(No longer issued) and the Ak 4B variant, where the iron sights have been removed, and replaced with an Aimpoint CS red-dot reflex sight mounted on a permanently mounted picatinny rail. All Ak 4s are adapted to mount the M203 Grenade Launcher. Sweden has supplied Ak 4s to Estonia, Latvia, and Lithuania.
DIO G3 Bullpup: Iranian made bullpup variant of the G3.
G3A7A1: Turkish made variant of the G3A4.
Danish soldiers carrying the G3A5 variant.
Turkish officer with the G3A3 in Northern Iraq.
Greek soldiers in NBC gear with Greek-made G3s.
A Latvian soldier providing security for coalition forces with a Swedish-made Ak4 in Iraq, 2006.
Soldiers from the Portuguese Army, 2nd Mechanical Battalion in Bosnia-Herzegovia in INDEP-made G3s.
