- Specifications:
- Weapon nomenclature - Samozariadnyia
Karabina Simonova (SKS)
- System of operation - Gas, Semi-automatic
fire only
- Bolt type - one-piece, tipping,
rear-cocking
- Weight (loaded) - 8.8 lbs.
- Length, barrel - 20.34 inches
- Length, overall - 40.16 inches
- Feed device - 10-round, fixed, staggered
double-row box magazine
- Sights, front - Hooded post
- Sights, rear - Tangent leaf, graduated from
100 to 1000 meters
- Cartridge - 7.62 x 39 Soviet M43 (Type PS
ball)
- Muzzle velocity - 2411 fps
- Bullet weight - 122 gr.
- Working pressure - 45,000 psi
- Bore diameter - .301 inches
- Groove diameter - .311 inches
- Direction & rate of rifling twist -
Right, 1 turn in 9.45 inches
Design History:
The SKS was adopted by the Soviet
Union in 1946, and is the basis for the later AK
series of weapons. It is a gas-operated,
semi-automatic rifle and might be referred to as
a miniature version of the 14.5mm PTRS
semi-automatic antitank rifle used during World
War 2. Both the SKS and the PTRS were designed by
the famed Russian arms inventor Sergei Simonov.
Because of its light recoil and moderate weight,
35 rounds per minute of aimed fire can be
achieved.
Unlike its predecessor, the
Tokarev, the SKS features an instantly
dismountable gas system. The gas cylinder is an
integral part of the handguard and contains the
piston rod. The front end of the combined gas
cylinder and handguard fits over a gas port
housing pinned to the barrel approximately 7
inches from the muzzle. The rear end butts
against the rear sight base which contains the
tappet rod and tappet rod return spring. The
latch located on the right side of the sight
serves to lock the handguard-gas cylinder into
place. Its removal for field maintenance takes
less than three seconds.
In the 1950's, Soviet
technical advisors helped the Chinese government
to establish several factories to produce the SKS
carbine. The first Chinese SKS carbines were
identical to their Soviet counterparts, and were
adopted by the Peoples Republic of China as the
Type 56 carbine. Subsequently, the Chinese have
manufactured several varieties of the original
SKS, including selective-fire models,
short-barreled "paratrooper" models,
and models which use the detachable magazine of
the later AK-47 assault rifle.
As the general availability of
the AK-47 improved in the early 1960's, the
SKS was relegated to the category of a secondary
military arm in both the USSR and in the PRC.
However, stockpiles of millions of SKS carbines
are maintained for the "Peoples
Militias" (strategic reserve) and for export
to the third world countries as "military
aid".
Operation:
When the rifle is fired, gas
enters the gas port housing under pressure to
thrust the piston rod back against the short
tappet rod. In moving back, the tappet rod slides
through a hole in the rear sight base and a
corresponding one in the top of the receiver to
strike the bolt carrier.
The claw-like arrangement of the
bolt carrier cams the rear end of the bolt
upward, unlocking it completely after 7/16"
of rearward travel. The kinetic energy imparted
to the bolt carrier upon being struck by the
tappet rod is sufficient to cause the bolt and
bolt carrier to travel together 3 7/8"
rearward to extract and eject the fired case and
to compress the recoil spring.
The compressed recoil spring
forces the bolt and carrier forward to strip a
cartridge from the magazine and chamber it. The
camming surfaces within the bolt carrier force
the rear end of the bolt down into the locked
position. When locked, the lower rear end of the
bolt butts against a hardened steel crosspiece
set within the receiver.
Description:
SKS carbines have been fitted
with two different styles of bayonet. The earlier
type is 9" in length and resembles a knife
blade. The later type is 12" long, and is
needle shaped. Both types are attached to the
barrel and fold back under the barrel when not in
use. The stock and handguard of the Soviet and
Eastern bloc carbines are made of laminated
beechwood with a hard, waterproof, clear lacquer
finish. Chinese-made SKS carbines are usually
found with stocks and handguards made of a porous
Asian hardwood resembling teakwood, and brushed
with an orange colored shellac-type finish. The
Chinese SKS is sometimes fitted with a synthetic
plastic resin stock and handguard which is molded
in a reddish-brown color.
The buttstock of all versions is
hollowed out to receive a cleaning kit contained
in a steel capsule. The body of the capsule also
serves as a handle for the cleaning rod and its
lid fastens over the muzzle to protect the rifle
during cleaning. Inside the capsule is a bore
brush, a cleaning rod extension, and a tool to
clear carbon fowling from the gas port. The
capsule lid can also serve as a blank firing
device, if properly locked onto the front sight
base.
The magazine is unusual and
consists of a stamped and welded sheet metal
housing, stamped sheet metal floor cap, and a
sheet metal follower. Both the follower arm and
the floor cap are hinged to the forward end of
the magazine body. A coil spring set at the hinge
point furnishes sufficient pressure to the
follower arm to insure the feeding of
cartridges.
The weapon is loaded from above
with ten-round stripper clips for which a guide
groove has been provided in the forward face of
the bolt carrier. It is important to exert thumb
pressure against the cartridges as close to the
clip as possible, since pressure applied
elsewhere makes it difficult to strip the last
three rounds. The stripper clip is a one-piece,
spring steel stamping - very sturdy and
efficient. The magazine can also be loaded with
single rounds.
Field
Stripping:
To unload the weapon for field
stripping, rapid emptying of the magazine is
accomplished by holding one hand under the floor
cap to catch the loaded rounds as the other hand
pulls back the magazine latch. After clearing the
chamber and detaching the sling, swing the latch
on the right side of the rear sight upward to the
first stop.
The gas cylinder-handguard can be
removed by lifting up at the rear and withdrawing
it from its forward contact with the gas port
housing. By swinging the latch up to its second
stop, the plunger and spring can be released
easily, but maintain thumb pressure against the
tappet rod to prevent it from being expelled by
the tappet rod spring.
NEVER, under any
circumstances, attempt to fire this weapon
with the handguard-gas cylinder removed, or with
a defective handguard latch! The gas port is
angled to point directly toward the shooters face
and severe injury will result from high pressure
gas and flame. The handguard-gas cylinder must be
firmly latched in place before
firing.
To dismantle the bolt assembly,
lower the bolt on the cleared chamber leaving the
hammer cocked, and locate the latch on the right
rear of the receiver. Rotate this latch until it
is upright and pull it out as far as possible.
Remove the receiver cover by lifting it and
pulling it to the rear. The recoil spring is
removed by drawing it rearward out of the bolt
carrier. By pulling the charging handle to the
rear and upward, the bolt and bolt carrier will
be freed from the receiver.
To remove the trigger group, push
the safety lever into the "safe"
position. Insert the bullet point of a loaded
round in the pocket of the spring catch located
directly behind the triggerguard and push
forward. The trigger group will become unfastened
and jump outward, pushed by a coil spring set
into the stock beneath the triggerguard.
Swing the trigger group downward
and back to remove. Pull the magazine group down
and to the rear to release it. Pull the handle of
the bayonet towards the blade to unlatch it.
Remove the cleaning rod by flexing it slightly to
release it from its slot beneath the front sight.
Pivot the bayonet until it locks in the extended
position. Grasp the receiver cover latch pin, and
use it to lift the receiver up and out of the
stock.
By reversing these steps, the
weapon can be reassembled. However, the following
precautions must be observed. Reseat the fore-end
of the stock properly within the barrel band.
When replacing the magazine, its forward end must
engage the lug extending from the rear sight
beneath the barrel.
Hinge the magazine cap upward and
hold it in this position while guiding the
projecting pins of the trigger group into the
receiver lug. Apply pressure to the bottom of the
triggerguard; if the trigger group does not lock
into place, brace the carbine with one hand and
deliver a sharp blow to the triggerguard to
insure proper seating. Before installing the
trigger group, the hammer must be in the cocked
position, and the safety must be engaged.
Ammunition:
Surplus military ammunition from
Com Bloc nations is currently banned from
importation. Some ammunition imported before this
ban is still available. Winchester (USA) and
Remington (UMC) supply military ball type ammo in
7.62x39 which is superior to Com Bloc ball.
Trajectory data supplied here is generic and
presumes a maximum point blank range (bullet
remains within 6 inches of line of sight) of 300
yards:
Distance (yards) |
25 |
100 |
200 |
300 |
400 |
500 |
Trajectory (inches) |
.7 |
4.7 |
2.1 |
-6.1 |
-26.6 |
-60 |
As can be seen from the table,
bullet drop makes obtaining hits with the 7.62x39
at ranges beyond 350 yards increasingly
difficult. Energy loss also limits effective
range.
Identifying Soviet Bloc 7.62 x 39
ammunition:
Designation |
Bullet Type |
Marking |
Round Weight |
PS |
Ball |
none |
256.8 gr. |
T-45 |
Tracer |
Green |
240.7 gr. |
Z |
Tracer-Incendiary |
Red |
239.8 gr. |
BZ |
AP Incendiary |
Black & Red |
251.5 gr. |