Proper and rapid cartridge extraction has long been one of the problem children
of ordnance design. Many of the stoppages prevalent in automatic and semiautomatic
weapons may be traced directly to extraction troubles. Many methods of achieving
proper extraction have been tried, involving numerous changes in the design of
cartridges, chambers, and extractors. Experiments have been carried on to develop
cartridges that will be consumed in the firing, thus doing away with extraction
altogether. (See Intelligence Bulletin, April 1946.)
Not altogether a new system, but a reasonably effective means of aiding extraction is
demonstrated in the chamber design of the Tokarev series of Soviet rifles. Although
the principal cause of faulty extraction in automatic weapons has been the unlocking of
the breech under pressure, some fault lies in the undue expansion of the cartridge
case against the walls of the chamber, thus making the cartridge case difficult to
remove, and forcing the use of heavily built extractors. The Russians have, in some
measure, compensated for this expansion by manufacturing chambers which are longitudinally
fluted instead of smooth. A fluted chamber throat is one which, instead of being smooth,
has small grooves cut into the walls. These grooves are passages into which a portion of
the propellent gases escape when the cartridge is fired. When the gases, at the instant
of firing, enter the grooves, they tend to equalize the forces on the inside of the
cartridge, thus reducing the adhesion of the cartridge case to the chamber walls. The
cartridge, then being less tight in the chamber, may be extracted with less effort and in
smoother action. Lighter extractors may be used, and broken extractors and jammed empty
cartridge cases are less frequent.
The German FG42 (Paratroop rifle 42) and some issues of the MP44 make use
of the same principle in that they have chambers that permit escape of gases around the
cartridge case, though the chamber throats of these German weapons are not fluted as is
that of the Russian M1940 Tokarev rifle, but rather are of larger diameter for
approximately one-half of the rear half of the chamber.
A description of the Tokarev rifle, Model 1940, may be of interest as being somewhat
indicative of trends in Russian design.
The Russian Tokarev Semiautomatic Rifle, M1940, is a 7.62-millimeter
(cal. .30) gas-operated, air-cooled, magazine-fed, shoulder weapon. The bulk
of the M1940's are capable only of semiautomatic fire. In 1942, in order to provide a
light antiaircraft weapon, a certain proportion of selective trigger groups, allowing
the weapon to fire on full automatic, replaced the old trigger groups, and a
15-round magazine was introduced in place of the old 10-round
magazine. However, the weapon
was only allowed to fire full automatic on order of the unit commander.
|The Tokarev M1940 semiautomatic rifle.|
Workmanship in the rifle is good, but it lacks the ruggedness that is evident in
U.S. design. This is primarily due to the Soviet attempt to make a rifle of
light weight. In order to eliminate extra weight, the barrel and receiver are
manufactured from very thin stock. The receiver walls are very easily bent putting
the weapon out of action. This has its drawbacks, as the maximum permissible continuous
fire (bursts) is only 30 rounds, or two magazines. Fifty rounds fired in continuous
bursts will generally ruin the rifle. The stock, too, has been made of light
woods, and is kept dry rather than oiled. All this has resulted in a rifle of light
weight—only 8.6 pounds with an empty magazine.
Effective rates of fire are considered to be 20 to 25 rounds per minute in
semiautomatic fire, and 70 to 80 rounds per minute when the rifle is fired on
The weapon develops a muzzle velocity of 2,720 feet per second when M1908 ball
ammunition is used. The maximum effective range is considered to be 440 yards
against ground targets, and 500 yards against strafing planes.
Unlike the U.S. M1 which has the gas chamber and operating rod placed
below the barrel, the Tokarev has the gas chamber, cylinder, and operating
rod above the barrel. This assembly is covered by a hand guard. A gas regulator
with five different apertures may be adjusted by means of a small
wrench, without disassembly of the piece.
A six-baffle combination muzzle brake compensator is permanently mounted on the
muzzle. This helps keep the muzzle down and lessens the recoil, but the back blast
from the gases produces a very bad effect on the firer in a comparatively short
time. Over-all length is 48.2 inches, not including the bayonet of 9.5 inches.
The front sight is a threaded post type, equipped with a hood which is a part of
the sight base. The rear sight is of the Mauser tangent leaf on ramp type with an
open U notch. The leaf is graduated from 100 to 1,500 meters, and is elevated
by means of a slide moving on a ramp.
In the rifles modified to fire semi- or full automatic the safety lever at the
rear of the trigger guard is also used as a change lever. When turned to the
left, uncovering the letter "O," the rifle will fire single shots; when turned
to the right, uncovering the letter "A," the rifle is set to fire full automatic;
when the lever is placed in a vertical position, the rifle is "safe."
There are very few moving parts in the rifle. The bolt operates straight
to the rear, and has no turning action. The locking action takes place when
the locking lugs on the rear of the bolt are forced down into a locking recess
by the bolt housing.
A convenience that will be appreciated by everyone who has had to clean a rifle for
inspection is a type of swinging cap on the rear of the receiver. This cap may
be rotated to permit cleaning the rifle from the breech end. Of course, this
little feature also makes it much easier for the inspecting officer to see a
dirty bore. The cleaning rod, incidentally, is carried in a groove on the right
side of the stock.
With the inclusion of a 3.5 X telescope that is easily mounted with a horseshoe
type mount, the rifle may be used for sniping.
Red Army doctrine for using this weapon is closely parallel to U.S. Army theory
in regard to automatic rifles. It is interesting to note, however, that Red Army
regulations forbid full automatic fire except on order of the commanding officer.