7.62-mm SVD
DRAGUNOV SNIPER RIFLE
TECHNICAL DESCRIPTION
AND SERVICE MANUAL
1.4. Design and operation 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.
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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.
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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 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" "Upward", "BHN3" "Downward", "CTn"
"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 0 01. 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
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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
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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 to 1200 m, the peak of the forth angle mark to 1300 m.
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Fig. 9. Field of vision view:
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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
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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
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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,
2. SERVICE MANUAL
CONTENTS
