7.62-mm SVD
DRAGUNOV SNIPER RIFLE
TECHNICAL DESCRIPTION
AND SERVICE MANUAL
1.4. Design and oper
ation of rifle



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| Fig. 2. 7.62-mm Dragunov sniper rifle:1 -
bolt support; 2 - firing pin; 3 - cover; 4- guiding rod; 5 - guiding
bushing; 6 - bolt;7 - extractor pin; 8 - firing pin stud; 9 - extractor
spring; 10 - extractor; 11 - return spring; 12 - sight leaf slide;
13 - sight leaf; 14 - hand guard, L.H. ; 15 - pusher spring; 16 -
gas tube latch; 17 - gas chamber; 18 - gas piston; 19 - gas tube
6B1; 20 - gas regulator; 21 - front sight body; 22 - front; 23
- pusher; 24 - front sight base; 25 - barrel; 26 - upper band,
assembly; 27 - band axle pin; 28 - oil seal, assembly; 29 - hand
guard, R. H. ; 30 - upper band with spring; 31 - magazine body,
assembly; 32 - magazine spring; 33 - magazine cover; 34 - sight
leaf, assembly; 35 - follower; 36 - receiver; 37 - accidental shot
safety device; 38 - firing and trigger mechanism; 39 - cover axle
pin; 40 - butt assembly. |
1.4.1. The sniper rifle consists of the following main parts
and mechanisms (Fig. 2):
- barrel with receiver;
- bolt with bolt support;
- safety lever, assembly;
- firing and trigger mechanism;
- cover with retracting mechanism;
- magazine;
- butt;
- upper band, assembly;
- hand guard, L.H., assembly;
- hand guard, R.H., assembly;
- sight leaf, assembly;
- front-sight base and body, assembly.
1.4.2. The sniper rifle is a self-loading weapon. The reloading
of the rifle is based on utilizing the energy of powder gases which arc
channeled from the barrel bore to the gas piston.
Upon firing, a certain amount of the powder gases following the bullet
flows through the port in the barrel bore wall into the gas chamber, exerts pressure
upon the front wall of the gas piston and throws back the piston with pusher
and, consequently, the bolt support into the rearward position.
As the bolt support travels rearward, the bolt opens the barrel bore,
the. cartridge case gets removed from the cartridge chamber and ejected out of
the receiver. The bolt support compresses the return springs and cocks the hammer,
i. e. engages it with the auto-safety cocking cam.
The bolt support and the bolt return to the front position under the action
of the retracting mechanism; as a result, the bolt feeds the next cartridge from
the magazine into the cartridge chamber and closes the barrel bore, while the
bolt support disengages the auto-safety sear from the hammer. The hammer gets
cocked. The bolt gets locked, after it has been turned to the left and its locking
lugs engaged with recesses of the receiver.
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| Fig. 3. Carrier for optical sight and magazines. |
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| Fig. 4. Bag for SPTA. |
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| Fig. 5. Sling for carrying small arms. |
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| Fig. 6. Slip cover for sight. |
To fire a shot, it is necessary to release the trigger and press it anew.
After the trigger has been released, the rod moes forward and its hook engages
the sear and, if pressed, the rod hook turns the sear and disengages it from
the hammer cocking cam.
The hammer actuated by the mainspring turns round its pin and strikes
the firing pin. The latter travels forward and impinges the primer. Thus, a shot
is fired.
With the last cartridge fired and the bolt returned to the rearward position,
the magazine follower lifts the bolt catch, the latter engages the bolt to stop
the bolt support in the rearward position. Thus, it is necessary to load the
rifle anew.
The rifle has a gas regulator, which serves to change recoil speeds of
moving parts. Under conditions of proper servicing with the parts lubricated,
the gas regulator is set at division 1. On firing during a long time without
cleaning and lubricating and heavy soiling of the rifle, stoppage may occur љ incomplete
recoil of the moving parts. In this case the regulator is set at division 2.
To change the regulator from one position to another use the rim of the cartridge
case or the cartridge.
1.5. Design and operation of sight and its component parts
1.5.1. The sniper optical sight PSO-1 (Fig. 7) consists
of the following main parts:
- body;
- objective;
- eyepiece;
- blind;
- eye shield;
- knob with the scale of sight angles;
- knob with the scale of deflection corrections;
- handle;
- coloured glass;
- guide;
- supply source;
- lamp;
- cap.
The objective in a mount with a collapsable blind is screwed into the
body. The eyepiece in assembly with the eye shield is screwed into the body from
another end.
On the top of the body is a knob with a sight angle scale plotted on its
cylindrical portion.
Inscriptions "BBepx" љ "Upward", "BHN3" љ "Downward", "CTn" љ "MPI" and
arrows, indicating the direction of the knob rotation when adjusting the sight
are plotted on the knob nut.
The sight angle scale is provided with ten divisions (from 0 to 10).
The value of the scale division equals to 100 m. Beginning from division
3 it is possible to set sight angles every 50 m using the knob retainer.
On the right side of the body there is a knob with the scale of deflection
corrections. The cylindrical portion of the knob is provided with 21 divisions
(from 0 to 10 in both directions).
Dash lines and digits located to the right from 0 are of a black colour,
and those located to the left from 0 are of a red colour.
The value of the scale division equals to 0љ01. Deflection corrections
may be set every 0-00.5 by means of the knob retainer.
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| Fig. 7. Sight PSO-1: 1 - blind; 2 -
objective; 3 - coloured glass; 4 - handle; 5 - nut; 6 - knob;
7 - body; 8 - eyepiece; 9 - eye shield; 10 - cap; 11 - cap |
Inscriptions "BnpaBo - To the Right", "BJieBo - To the
Left", "CTn - MPI" and arrows, indicating the direction of rotation,
when adjusting the sight are plotted on the nut fastening the knob of the deflection
correction mechanism.
The band of the sight angle knob, as well as the band of the deflection
correction knob each bears 60 divisions. The value of one division equals 0-00.5.
Divisions on knob bands serve for reading the correction when adjusting the sight
on the rifle.
The power source of the illuminating lamp is located in the seat of the
body. The seat is covered with a cap.
1.5.2. The sight optical system is designed for obtaining images
of objects, located on the terrain and represents the monocular telescopic system
with permanent magnification.
The optical system (Fig. 8) consists of objective lenses, reticle, reversing
system, eyepiece lenses, screen, coloured glass, light-orange glass and protective
glass.
The objective is designed for obtaining the image of the observed object.
In an objective focal plane an image is obtained reversed from the left to the
right and from the top to the bottom.
The reversing system is intended to obtain the real correct image.
The eyepiece serves to inspect an observed image and reticle.
The light-orange coloured glass improves contrast of an image in a dull
weather.
The reticle represents a flat-parallel plate. The plate is provided with
the scales of sight angles and deflection corrections as well as a range-finding
scale. The field of vision view is shown in Fig. 9.
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| Fig. 8. Optical scheme: 1, 2 - objective
lenses; 3 - welded screen; 4 - reticle; 5, 6 - lenses (relay-lens);
7, 8 - eyepiece lenses; 9 - light-orange coloured glass; 10 -
coloured glass; 11 - protective glass |
The sight angle scale represents a number of angle marks up to the range
of 1300 m. When setting the sight angle knob scale at division 10, the
peak of the second from the top angle mark will correspond to the range
of 1100 m, the peak of the third angle mark љ to 1200 m, the peak
of the forth angle mark љ to 1300 m.
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| Fig. 9. Field of vision view: |
Plotted to the left and to the right from the angle marks is the scale
of deflection corrections. The value of each division is 0-01.
The values of deflection corrections 0-05 and 0-10 are marked out by an
elongated dash line. The value of deflection correction 0-10 is marked out by
an elongated dash line and designated by a digit 10. Two horizontal dash lines
are plotted from the right and from the left of the deflection correction scale.
The range-finding scale located from the left under the deflection correction
scale serves for detecting the range up to the target. The range-finding scale
represents two lines. The upper (curve) line is calculated for a target 1.7 m
in height and is marked with digits 2, 4, 6, 8 and 10.
The sight reticle is displaced in two directions which are perpendicular
to each other, but it is always remains in an objective focal plane.
* Note. It is possible to complete the rifle with the sight
of PSO-1М2 make without the screen, coloured glass and handle.
1.6. Sniper rifle accessories
1.6.1. The sniper rifle accessories (Fig. 10) are used
in disassembling, cleaning and lubricating the sniper rifle and are carried
in the bag intended for the sight and magazines.
1.6.2. The set of accessories includes: a cheek plate, a cleaning
rod, a scourer, a bristle brush, a screwdriver, a drift, a container and an oiler.
THE CHEEK PLATE is used when firing the rifle with the optical
sight. In this case it is put on the rifle butt and fixed on the latter by means
of the lock.
THE CLEANING ROD is used to clean and lubricate the barrel bore,
passages and cavities of other parts of the rifle. The cleaning rod consists
of three sections screwed to one another.
THE SCOURER is used for cleaning and lubricating the barrel bore
as well as the passages and cavities of other rifle parts.
THE BRISTLE BRUSH is intended for cleaning the barrel bore with
the RCHS solution.
THE SCREWDRIVER is used in disassembling, assembling the rifle
and in cleaning the gas chamber and the gas tube. It is also used as a wrench
to adjust the front sight position in height.
THE DRIFT is used for driving the pins and studs out.
THE ACCESSORIES CONTAINER houses the scourer, the bristle brush,
the screwdriver and the drift. It consists of two component parts: a container-wrench
and a cover.
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| Fig. 10. Accessories to rifle: 1 - container
cover; 2 - bristle brush; 3 - screwdriver; 4 - scourer; 5 - drift;
6 - container body; 7 - oiler; 8 - cheek plate; 9 - cleaning
rod; 10 - cleaning rod extender; 11 - cleaning rod extender,
front |
The container-wrench is used as a handle of the cleaning rod, when cleaning
and lubricating the rifle and as a handle of the screwdriver when disassembling
and assembling the rifle, and as a wrench when detaching the gas tube and assembling
the cleaning rod.
THE CONTAINER COVER is used as a muzzle protector in cleaning the
barrel.
THE OILER is used for storage of the lubricant.
1.7. Individual SPTA set to sight
1.7.1. Individual SPTA set (Fig. 11) serves for providing normal functioning
of the sight and replacement of separate failed parts.
1.7.2. Individual SPTA set includes: illuminating system, coloured
glass, wrench, napkin, supply sources, (sections 2RC63), lamps (in cassette)
and a cap.
** Notes. 1. One of the sections is placed into the sight.
2. The napkin is not shown conventionally.
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| Fig. 11. Sight PSO-1 with individual SPTA
set: 1 - wrench; 2 - sections of mercury-zinc cells 2RC63;
3 - coloured glass; 4 - lamps CM 2.5-0.075 (in cassette); 5
- cap; 6 - illuminating system |
The illuminating system is intended for lighting the reticle when working
with the sight at the environmental temperature below 0 grad. С.
The wrench serves for screwing the reticle illuminating lamp in and out.
The napkin is intended for cleaning optical parts.
Supply source, lamps and a cap are delivered as spare parts.
1.8. Tare and packing
1.8.1. The sniper rifles are supplied to the Customer
in wooden chests painted in khaki colour. In each chest six sniper rifles
with all completing articles are placed and fastened with special inserts.
1.8.2. The chest is composed of two compartments separated with
a wooden partition. The bottom as well as all walls of the chest are covered
with paraffined paper. Prior to packing, the bottom and walls of the large compartment
of the chest are additionally covered with inhibited paper. The small compartment
of the chest is not covered with inhibited paper. The optical sights and slings
for carrying small arms which are packed in this compartment are wrapped only
with paraffined paper,