PSO-1

The PSO-1 (Прицел Снайперский Оптический, Pritsel Snaipersky Optichesky, "Optical Sniper Sight") is a telescopic sight manufactured in Russia by the Novosibirsk instrument-making factory (NPZ Optics State Plant) and issued with the Russian military Dragunov sniper rifle.

The PSO-1 was, at the time of its introduction around 1964, the most technically advanced telescopic sight ever designed for a mass-production designated marksman or sniper rifle.

The PSO-1 was specifically designed for the SVD as a telescopic sight for military designated marksman activities. The current version of the sight is the PSO-1M2. This telescopic sight is different from the original PSO-1 only in that it lacks the now obsolete infrared detector. The metal body of the PSO-1 is made from a magnesium alloy. The PSO-1 features a battery-powered red illuminated reticle with light provided by a simple diode bulb. It features professionally ground, fully multi-coated optical elements, a baked enamel finish for scratch protection, and an attached, quick-deployable, extendable sunshade.

The scope body is sealed and filled with nitrogen, which prevents fogging of optics and was designed to function within a -50 °C to 50 °C temperature range. For zeroing the telescopic sight the reticle can be adjusted by manipulating the elevation and windage turrets in 5 cm at 100 meters (0.5 mil or 1.72 MOA) increments.

Considered the higher end of Soviet military side-mount telescopic sights, the quality of the PSO-1 is higher than most other PSO-style telescopic sights. The PSO-1 has neither a focus adjustment nor a parallax compensation control. Most modern military tactical scopes with lower power fixed magnification such as the ACOG, C79 optical sight or SUSAT (intended for rapid close-intermediate range shots rather than long-range sniping) lack such features as well. Modern fixed magnification military high-end-grade sniper telescopic sights scopes intended for long-range shooting usually offer one or both of these features. The positioning of the scope’s body to the left of the bore’s center line may not be comfortable to all shooters.

The PSO-1 elevation turret features bullet drop compensation (BDC) in 50 m or 100 m increments for engaging point and area targets at ranges from 100 m up to 1,000 m. At longer distances the shooter must use the chevrons that would shift the trajectory by 100 m per each chevron. The BDC feature must be tuned at the factory for the particular ballistic trajectory of a particular combination of rifle and cartridge at a predefined air density. Inevitable BDC-induced errors will occur if the environmental and meteorological circumstances deviate from the circumstances the BDC was calibrated for. Marksmen can be trained to compensate for these errors.

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