PU scope
The PU (Russian: прицел упрощённый, "simplified sight") scope is a compact 3.5× telescopic sight of Soviet manufacture, introduced in 1940 and designed initially for the SVT-40 semi-automatic rifle, later adapted for the Mosin-Nagant M1891/30 bolt-action rifle as the primary Soviet sniper optic during World War II.[1] With a 20 mm objective lens, 169 mm length, and weight of approximately 270 grams, it featured simple friction-adjustable turrets for elevation and windage, a slender post reticle, and a side-mounted bracket system for rugged field use, prioritizing reliability over high magnification in harsh combat conditions.[2] Development of the PU scope originated at Factory No. 3 in Kharkov as an initiative to create a more practical alternative to the earlier 4× PE scope, which proved cumbersome during the Winter War.[1] Production ramped up across multiple factories, yielding over 552,000 units by January 1945, with the scope mounted on hundreds of thousands of Mosin-Nagant sniper rifles from 1942 onward.[1][3] Its design emphasized simplicity and manufacturability, with internal anti-reflection threading on the objective lens and varying turret configurations to suit wartime demands, making it resistant to fogging and damage compared to predecessors like the PEM scope.[1] In military application, the PU scope equipped Soviet snipers on the Eastern Front, enabling effective engagements up to 600 meters or more with the 7.62×54mmR cartridge, and was instrumental in the Red Army's extensive sniper training program that produced thousands of marksmen, including notable figures like Vasily Zaytsev during the Battle of Stalingrad.[2] Postwar, it saw continued use on machine guns and in trials, influencing later Soviet optics, while its legacy endures in replicas and collector interest for its role in one of history's largest sniper forces.[1]History
Development
The Soviet Union sought a compact telescopic sight for sniper rifles in the late 1930s to address the limitations of the existing PE and PEM scopes, which were too bulky and interfered with the ejection port of the new SVT-40 semi-automatic rifle.[3] These earlier scopes, weighing approximately 625 grams and measuring longer in overall length, proved impractical for mounting on the SVT-40 without compromising the rifle's operational reliability.[4] The PU scope was designed as a smaller and lighter alternative, at about 270 grams and 169 mm in length, enabling seamless integration with the semi-automatic platform.[5] Development of the PU scope began in early 1940 at Factory No. 3 (NKVD) in Kharkov, Ukraine, as a factory initiative without a direct government order.[1] Engineers at the Kharkov facility produced a simplified, robust sight suitable for mass production under wartime constraints, focusing on a fixed 3.5× magnification to optimize the balance between a wide field of view for target acquisition and sufficient precision for sniper engagements at typical combat ranges.[6] Initial testing of the PU scope occurred in May 1940 on SVT-40 prototypes, evaluating its mounting compatibility and optical performance in field conditions, which led to its official adoption by the Red Army later that year as the standard sniper optic for the SVT-40.[7] This transition marked a shift from the PE series' 3.87× magnification and side-mounted configuration, prioritizing compactness for semi-automatic rifles while maintaining effective sighting for infantry snipers.[8]Production
Mass production of the PU scope commenced in the autumn of 1940 at Factory No. 3 (also designated NKVD No. 3, later NKAP No. 296) located in Kharkov, Ukraine, following its official acceptance by Soviet military authorities on July 18, 1940.[1] This facility, evacuated to Berdsk in 1941 due to the advancing German forces, initially produced scopes primarily for the SVT-40 rifle, with output reaching 5,675 units in 1940, 17,786 in 1941, and approximately 2,500 in 1942 before halting PU production that summer.[1] To meet escalating wartime demands, additional factories were brought online, including Factory No. 297 in Yoshkar-Ola, which began manufacturing in March 1943 and focused exclusively on scopes for the Mosin-Nagant M1891/30 rifle, producing 34,800 units in 1943 and 56,817 in 1944.[1] Annual production peaked during 1943 and 1944 to support the surging need for sniper equipment on the Eastern Front, with total output across all facilities exceeding 230,000 scopes in 1943 (including 115,683 from Factory No. 357 in Omsk) and approximately 197,000 in 1944 (including 105,009 from the same factory).[1] Other key contributors included Factory No. 237 in Kazan (39,007 total from 1943–1944) and Factory No. 393 in Krasnogorsk (80,541 from 1943–1944), alongside continued output from Factory No. 357, which alone accounted for over 57% of wartime PU scopes at 315,473 units from 1940 to 1945.[1] Overall, more than 550,000 PU scopes were manufactured during the war years through 1945, reflecting the Soviet Union's rapid industrialization of optical production under duress.[1] Wartime material shortages prompted adaptations in construction, with the standard steel tube body supplemented by silicon-aluminum alloy (silumin) for the objective lens assembly in PU-43 scopes produced at Factory No. 393; however, this practice was prohibited by the GAU in summer 1944 due to durability concerns.[1] Steel or other substitutes replaced traditional brass in some objective lens assemblies to conserve strategic metals, ensuring continued output despite resource constraints.[1] Early production batches in the 1940s faced quality control challenges, including alignment and mounting inconsistencies when initially paired with the SVT-40, which led to refinements by 1942 for better compatibility with the Mosin-Nagant M1891/30 rifle using the new Kochetov mount design.[1] These adjustments improved reliability and standardized testing protocols, with rifles and scopes required to pass evaluations by August 20, 1942.[1] Postwar, Soviet production tapered off after 1945, but scopes continued to be refurbished and exported to allies, including supplies to Poland where local reworkings adapted them for continued use into the 1950s.[9]Design
Optical system
The PU scope utilizes a fixed 3.5× magnification delivered by a compact refracting telescope design, prioritizing simplicity and mass production for wartime use. This optical system consists of a multi-element lens assembly, including nine lens elements—some air-spaced and others cemented—arranged in the objective and eyepiece to form a clear image while minimizing size and weight.[10][11] The objective lens measures 21 mm in diameter, paired with an eyepiece that provides an angular field of view of 4° 30', allowing effective target acquisition at typical sniper engagement distances. Eye relief is approximately 70 mm (2.7 inches), which accommodates the recoil of the host rifle while maintaining a comfortable sighting position. The exit pupil of about 6 mm supports adequate light gathering for low-light conditions prevalent on the Eastern Front, such as dawn or dusk operations, without specialized illumination.[11][12] The reticle features a simple post-and-crosshair pattern, with the heavy central post aiding quick target alignment under field conditions. This design is optimized for the ballistics of 7.62×54mmR ammunition, incorporating bullet drop compensation through vertical movement of the reticle via the elevation adjustment, enabling holdovers for ranges up to 1,300 meters without additional external references.[11][12]Mounting and adjustments
The PU scope was mounted using a side-mounted dovetail bracket system, known as the Kochetov mount for the Mosin-Nagant M91/30 rifle, designed by engineer D.M. Kochetov and adopted in 1942 following successful testing. This mount allowed for quick-detach installation on the left side of the receiver, secured via a dovetail base and screws, enabling removal and reinstallation without specialized tools while maintaining zero through factory-matched serialization on Izhevsk-produced rifles. For the SVT-40 semi-automatic rifle, an earlier side mount (model 1936) was employed, featuring an offset position to prevent interference with the bolt carrier during operation, whereas the Mosin-Nagant version utilized a rear-located bracket optimized for the bolt-action mechanism. Elevation adjustments were handled by a free-spinning turret drum on the top of the scope, graduated from 0 to 1,300 meters in 100-meter increments to correspond with ballistic drop for the 7.62×54mmR cartridge. The drum could be rotated smoothly without detents or clicks, relying on internal friction to lock the setting in place for battle zeroing, typically set to the "1" mark for a 100-meter zero; coarse elevation was further refined via screws on the mount base if needed. One full revolution of the mount's elevation screws corresponded to approximately 1 yard of point-of-impact shift at 100 yards. Windage corrections were made using a side-mounted screw adjustment, calibrated in milliradians (mils), with markings allowing for precise drift compensation; the mechanism provided a total adjustment range sufficient for environmental factors, though exact limits varied by production but generally supported up to several mils left or right without exceeding the scope's mechanical travel. Like the elevation turret, it operated without audible clicks, held by friction, and fine-tuning could involve shimming or filing the mount's contact points for initial alignment. The PU scope featured a fixed parallax setting at 100 meters, lacking a focus ring to simplify design and reduce weight, which minimized aiming errors at the primary engagement distance but introduced minor parallax at longer ranges. Diopter adjustment was provided at the eyepiece via a rotating ring, allowing users to compensate for individual eyesight variations and achieve sharp reticle focus without altering the optical path.Specifications
Key parameters
The PU scope, as the standard model employed on Soviet sniper rifles during World War II, features compact dimensions optimized for integration with the Mosin-Nagant M91/30 and SVT-40 platforms. Its length measures 169 mm, with a total weight of approximately 270 g for the scope, contributing to its portability and balance on the rifle.[2] Optically, the scope provides a fixed magnification of 3.5×, paired with a 20 mm objective lens diameter and a 6 mm exit pupil diameter, enabling clear target acquisition in varied lighting conditions typical of battlefield use. The angular field of view is 4.5°, corresponding to an approximate linear width of 7.9 m at 100 m distance, which balances situational awareness with precision aiming.[2][11] Adjustment capabilities include an elevation range calibrated from 0 to 1,300 m for ballistic compensation, and a windage adjustment totaling ±5 mils to account for crosswinds, with each click corresponding to fine increments for accurate zeroing. These ranges are marked directly on the turrets for quick reference during engagements.[1] Environmentally, the PU scope is waterproof for field use, ensuring functionality in wet conditions, and operates reliably across temperatures from -40°C to +50°C, reflecting its design for extreme Russian Front weather. It is also shock-resistant to the recoil of 7.62×54mmR cartridges, with a robust steel tube construction that withstands repeated firing without optical misalignment.[2]| Parameter | Specification |
|---|---|
| Length | 169 mm |
| Weight (scope) | ~270 g |
| Magnification | Fixed 3.5× |
| Objective Diameter | 20 mm |
| Exit Pupil | 6 mm |
| Field of View | 4.5° (7.9 m at 100 m) |
| Elevation Range | 0–1,300 m |
| Windage Range | ±5 mils |
| Operating Temperature | -40°C to +50°C |
| Shock Resistance | Rifle recoil (7.62×54mmR) |