The Dragunov sniper rifle (formally Russian: Снайперская
винтовка Драгунова, Snayperskaya Vintovka Dragunova (SVD), literally
"Dragunov's sniper rifle") is a semi-automatic sniper
rifle/designated marksman rifle chambered in 7.62×54mmR and developed in the
Soviet Union.
The Dragunov was designed as a squad support weapon, since
according to Soviet and Soviet-derived military doctrines the long-range
engagement ability was lost to ordinary troops when submachine guns and assault
rifles (which are optimized for close-range and medium-range, rapid-fire
combat) were adopted. For that reason it was originally named
"Полуавтоматическая винтовка Драгунова" Dragunov's Semi-automatic
Rifle.
It was selected as the winner of a contest that included
three competing designs: the first was a rifle designed by Sergei Simonov
(known as the SSV-58), the second design, a prototype designated 2B-W10 by
Alexander Konstantinov, and the third rifle, the SVD-137, a design submitted by
Yevgeny Dragunov. Extensive field testing of the rifles conducted in a wide
range of environmental conditions resulted in Dragunov’s proposal being
accepted into service in 1963. An initial pre-production batch consisting of
200 rifles was assembled for evaluation purposes, and from 1964 serial production
was carried out by Izhmash.
Since then, the Dragunov has become the standard squad
support weapon of several countries, including those of the former Warsaw Pact.
Licensed production of the rifle was established in China (Type 79 and Type 85)
and Iran (as a direct copy of the Chinese Type 79).
Operating mechanism
The Dragunov is a semi-automatic gas-operated rifle with a
short-stroke gas-piston system. The barrel breech is locked through a rotating
bolt (left rotation) and uses three locking lugs to engage corresponding
locking recesses in the barrel extension. The rifle has a manual, two-position
gas regulator.
After discharging the last cartridge from the magazine, the
bolt carrier and bolt are held back on a bolt catch that is released by pulling
the cocking handle to the rear. The rifle has a hammer-type striking mechanism
and a manual lever safety selector. The rifle's receiver is machined to provide
additional accuracy and torsional strength. The Dragunov's receiver bears a
number of similarities to the AK action, such as the large dust cover, iron
sights and lever safety selector, but these similarities are primarily cosmetic
in nature.
Features
The weapon is fed from a curved box magazine with a 10-round
capacity and the cartridges are double-stacked in a checker pattern.
The Dragunov's barrel is ended with a slotted flash
suppressor. The barrel’s bore is chrome-lined[3] for increased corrosion
resistance, and has 4 right-hand grooves with a 320 mm (1:12.6 in) twist rate.
The rifled part of the barrel is 547 mm (21.5 in). Later the twist rate was
tightened to 240 mm (1:9.4 in) which slightly reduces the accuracy of fire with
sniper cartridges and reduces the muzzle velocity to 810 m/s (2,657.5 ft/s).
This was done in order to facilitate the use of tracer and armor-piercing
incendiary ammunition. These special bullet types required a shorter twist rate
for adequate stabilization.[4]
For precision shooting, specifically designed sniper
cartridges are used, developed by V. M. Sabelnikov, P. P. Sazonov and V. M.
Dvorianinov. The proprietary 7N1 load has a steel jacketed projectile with an
air pocket, a steel core and a lead knocker in the base for maximum terminal
effect. The 7N1 was replaced in 1999 by the 7N14 round. The 7N14 is a new load
developed for the SVD. It consists of a 151 grain projectile which travels at
the same 830 m/s, but it has a sharp hardened steel core projectile. The rifle
can also fire standard 7.62×54mmR ammunition with either conventional, tracer
or armor piercing incendiary rounds.
The Russian military has established accuracy standards the
SVD and its corresponding sniper grade ammunition have to meet. Manufacturers
must perform firing tests to check if the rifles and sniper grade ammunition
fulfill these standards. To comply to the standards the SVD rifle with 7N1
sniper cartridges may not produce more than 1.24 MOA extreme vertical spread
with 240 mm twist rate barrels and no more than 1.04 MOA extreme vertical
spread with 320 mm twist rate barrels. When using standard grade 57-N-323S
cartridges the accuracy of the SVD is reduced to 2.21 MOA extreme vertical
spread. The extreme vertical spreads for the SVD are established by shooting
5-shot groups at 300 m range. The accuracy requirements demanded of the SVD
with sniper grade ammunition are similar to the American M24 Sniper Weapon
System with M118SB cartridges (1.18 MOA extreme vertical spread) and the M110
Semi-Automatic Sniper System with M118LR ammunition (1.27 MOA extreme vertical
spread).
The Dragunov has a vented, two-piece wooden handguard/gas
tube cover and a skeletonized wooden thumbhole stock equipped with a detachable
cheek rest; the latter is removed when using iron sights. Newer production
models feature synthetic furniture made of a black polymer - the handguard and
gas tube cover are more or less identical in appearance, while the thumbhole
stock is of a different shape.
Sights
The rifle features mechanically
adjustable backup iron sights with a
sliding tangent rear sight (the sight can
be adjusted to a maximum range of
1,200 m). The iron sights can be used with or without the standard issue
optical sight in place. This is possible because the scope mount does not block
the area between the front and rear sights.
The Dragunov is issued with a
quick-detachable PSO-1 optical sight. The PSO-1
sight (at a total length of 375 mm with a lens cover and sun shade, 4x
magnification and 6° field of view) mounts to a proprietary side rail mount
that does not block the view of the iron sight line. The PSO-1 sight includes a
variety of features, such as a bullet drop compensation
(BDC) elevation adjustment knob, an illuminated rangefinder grid, a
reticle that enables target acquisition in low
light conditions as well as an infrared charging screen
that is used as a passive detection system. The PSO-1 sight enables targets to
be engaged at ranges upwards of 1,300 m; effective ranges in combat situations
have been stated at between 600 to 1,300 m, depending on the nature of the
target (point or area target) quality of ammunition and skill of the shooter.
Several other models of the PSO
sight are available with varying levels of magnification and alternative aiming
reticulesRifles designated SVDN come equipped with a night sight, such
as the NSP-3, NSPU, PGN-1, NSPUM or the Polish passive PCS-6 and can be used to engage targets at
night.
Accessories
A number of accessories are provided with the rifle,
including a blade-type bayonet (AKM clipped point or the AK-74 spear point
bayonet), four spare magazines, a leather or nylon sling, magazine pouch,
cleaning kit and an accessory/maintenance kit for the telescopic sight.
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