GP Customs

Russian siderail scope adjustments POSP, PSO,1P21

Using the built-in range finder.
The reticle of the military
PSO and POSP scopes have a range finder that can be used to determine the
distance to a particular target. Some reticles are calibrated for targets from 1.5, 1.7, or 1.8 meters tall,
depending on type.** To determine your type of range finder look at the number near the bottom line of
the reticle.

Using the range finder.
Place the target on the bottom horizontal line of the range finder. Where ever the top of the target
touches on the sloping scale is the distance in meters you are from that target. The range finder scale is
limited to targets from 200 to 1000 meters away. Imagine a 5' 6” target is standing on the flat line under the rising graph and
using the 1.5 scale his head would intersect the elevating scale between the 2 and 3 mark slash meaning the target is about
250 meters away.
Once you know the distance to the target, adjust the elevation drum to the corresponding number (2 =
200, 3=300, etc.) in meters. From 0 to 3 each click on the elevation drum equals 100 meters, from 3 to
10 the clicks equal 50 meter increments.
Your elevation drum adjusts to 1000 meters. For targets beyond that, use the chevrons below the top
aiming point in the reticle. Each chevron represents an additional 100 meters in hold over.
Windage correction:
Because the scope is off-set to the rifle's bore, you may need to make a windage correction for
distances beyond your 100 meter zero. You have two options to accomplish this task. Either turn the
windage drum up or down or use the hash marks to the left and right of the center chevron in the
reticle. You simply “hold over” left or right, aligning your target over a particular hash mark. Each hash
mark represents one click on the windage turret which translates to 1.9 inches of movement at 100
*Remember your reticle and elevation drum is calibrated for a projectile around 150 grains and a
distance in meters not yards.
** 1.5 meters = 4.9 feet, 1.7 meters = 5.58 feet, 1.8 meters = 5.9 feet

IP21 however uses a military diopter for automatic ranging using a zoom wheel on its side.
The elevation and windage turrets are set once at 330meters and not touched again.
Compensation for drop and ballistics is based on a 15gr projectile in 7.62X54 caliber.
The reticle is designed to automatically zero on a known target either using the side wheel .
75m or
1.5m high with a .5m width at any distance from 300-900m. To zero in on a
target, bring the target within the limits of the rectangular or the top part of the
rectangular and the horizontal line by adjusting the zoom knob. Then the readout
mark at 12 o’clock will specify current magnification and the distance to the
target can be found by multiplying the magnification number by one hundred.
To zero on a target of different dimensions, find the distance to the target using
the horizontal aiming scale. Divide that horizontal distance by one hundred. By
rotating the zoom knob, put the corresponding number on the
Magnification/Range dial against the readout mark at the 12 o’clock position.
Russian POSP
Russian 1P21
Page 1
PG 1
PG 3
PG 4
PG 5
PG 6
PG 7
PG 8
Note: Before you start firing down range remember
to start at a close target so your hit paper first and
not earth.
I would suggest that you shot off of a lead
sled or fixed firing position at 50 yards before you
make your final adjustments for zero at your scopes
base line.
Your MOA means nothing until you have your POA
match your POI
Russian 1P21
PG 1
PG 3
PG 4
PG 5
PG 6
PG 7
PG 8