Ordnance
Notes -- by Bob Stoner GMCM (SW) Ret.
Heckler and Koch Gewehr 3 (G3) 7.62mm Rifle
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An
early H&K G3A3 rifle is shown here with the original “slim”
forearm. Navy SEALs made limited use of this G3A3 variant in Viet
Nam operations. (Photo: H&K)
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One
of the more common 7.62mm NATO main battle rifles is the H&K
G3-series. The G3 has been produced in numerous countries and has
served or serves with many armies, special operations forces, and
police organizations. The story of the G3 goes back to World War 2.
The
Germans were the first to introduce the world to the Sturm Gewehr
(StG) or assault rifle concept. They fielded numerous guns in their
7.92x33mm (7.92mm kurz or short) caliber. The most common were
the MP43 and MP44 series of rifles. At the time the war ended in
Europe, Dr. Ludwig Vorgrimmler and some other technicians at Mauser
were working on the StG45 which employed a radically different
locking system than that used by the MP43 and MP44. Dr. Vorgrimmler
and some of his technicians left Germany for Spain to continue
development of the StG45.
The
Spaniards were looking for a modern replacement for their bolt-action
Mauser rifles. However, they wanted a rifle with more range than the
7.92x33mm cartridge offered. In 1948 the Special Materials Technical
Studies Center (CETME) was established to pursue development of the
rifle and cartridge. By 1949 a prototype rifle was produced and by
1952 the new CETME rifle was being demonstrated in Spain and Germany.
While
the Spaniards were working on the CETME, the Germans were trying to
rebuild their country after its devastation in World War 2. In 1949
the North Atlantic Treaty Organization (NATO) was created and a new
German armed forces (Bundeswehr) was reborn. The Bundeswehr
was originally equipped with ex-American weapons, but the Germans
wanted a new rifle with advanced capabilities. The Germans contracted
for a new rifle, the Gewehr 1 (G1) with the Belgian firm of
Fabrique Nationale in Liege, Belgium. FN delivered 100,000 G1 rifles
to Germany to arm the Bundeswehr, but negotiations for a
licensing agreement to produce the rifle in Germany fell through. In
1957 both Germany and Spain adopted the CETME; in Germany the rifle
was known as the Gewehr 3 (G3) and in Spain as the CETME.
Getting the rifle into production resulted in the first of a series
of Spanish-German joint-development accords between Heckler and Koch
and CETME.
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A
CETME Model C 7.62mm NATO rifle in the hands of a Spanish National
Police guard at the American Embassy in Madrid. (Photo:
Cetmerifles.com) |
At
first, the rifle was produced in two calibers: the 7.62mm NATO for
Germany and the 7.62mm CETME. The later Spanish cartridge was
identical in size and shape to the German round, except for a reduced
powder charge. Both German and Spanish guns were marked with the
CETME logo until 1961, when it was dropped from the German gun. In
1964 the Spaniards standardized their CETME Model C rifles to fire
the 7.62mm NATO cartridge. The G3 and CETME rifles are quite similar
in appearance but there are subtle differences in construction and
finish between them. Most striking is the German use of plastics for
the butt stock, pistol grip and forearm; the Spanish preferred to use
the more traditional wood. German guns have a black epoxy finish,
while Spanish guns have a Parkerized (manganese phosphate) finish.
Both countries developed several versions of the G3 and CETME in
various calibers. H&K in Germany really pushed the concept of the
roller-locked breech for various guns. It designed whole families of
weapons in various calibers using the roller-locked breech concept
that have been marketed world wide.
The
weapon chosen by Navy SEALs for operations in Viet Nam was the
German-produced G3A3. The G3 is unique among the weapons standardized
by NATO during the 1950s as having the roller-locked breech mechanism
and fluted chamber. The receiver of the G3 is a stamping. The barrel
is pinned into a trunnion block (containing the locking recesses for
the bolt rollers) and the trunnion is pinned and welded into the
receiver stamping. The bolt of the G3 is composed of two parts: the
bolt head which contains the bolt locking rollers and the bolt
carrier which contains the firing pin and locking cam. The cocking
lever for the G3 is housed in a tube above the barrel. The cocking
lever is located on the left side of the tube near the front sight.
When the cocking lever is extended, the bolt carrier is moved back to
release the bolt rollers (this requires some effort) before the lever
can be pulled fully to the rear to load or clear the rifle.
Operation:
when the bolt chambers a cartridge, the bolt head (with locking
rollers retracted) enters the trunnion block. The following bolt
carrier closes and the locking cam extends the bolt rollers into
their locking recesses in the trunnion block. When the firing pin
fires the cartridge, the rollers hold the bolt locked in the trunnion
block until the pressure drops to acceptable levels. The G3 uses a
fluted chamber to float the cartridge case on propellant gases to
prevent the case from sticking to the sides of the chamber. Once the
pressure drops to a safe level, the bolt carrier moves back, the
locking cam retracts, and the bolt rollers move into the bolt head
(unlock). Extraction and ejection of the fired case from a G3 is very
positive and violent. Fired cases will typically show blackened,
longitudinal scorch marks around the diameter of the case and a dent
where the case has hit the edge of the ejection port. The G3 is a
select fire rifle and is very simple to maintain in the field. The
rifle is easily fitted with a quick-detachable telescopic sight or
night vision devices for special missions.
Heckler
and Koch G3A3 Specifications:
Caliber: 7.62x51mm NATO Length
-- 40.4 inches Barrel -- 17.8 inches Magazine -- 20
rounds Weight (empty) -- 9.7 lbs. Max. Effective Range -- 550
yards (limited by diopter sight)
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G3 receiver
section diagram shows the rifle ready to fire with the bolt
rollers locked. (Drawing: H&K) |
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G3 receiver
section diagram shows the rifle after firing with the bolt rollers
retracted, (Drawing: H&K) |
©
2005 Bob Stoner R3 |