Description
U.S. Army M71C Gunner’s Telescope for 90mm Gun M3 — T26E3/M26 Pershing and M36 Series
Item Overview
This U.S. Army Telescope M71C is a direct-fire optical sight developed for the vehicle-mounted 90mm Gun M3. The identification plate is marked “TELESCOPE M71C,” Stock No. 7578170, and Serial No. 9042. It provided 5× magnification and a 13-degree field of view, allowing the gunner to identify, track, and aim at targets through a graduated reticle. Wartime Ordnance records document the M71C with the T26E3 heavy tank that entered service as the M26 Pershing. A later Army vehicle reference also lists it as one of the telescopic sight options for the M36, M36B1, and M36B2 90mm gun motor carriages. This listing is for the telescope shown; no vehicle, gun, or complete sighting system is included.
Identification and Features
The M71C is a straight-tube telescope designed to move with the main gun during elevation and traverse. In the documented T25E1 and T26E1 installation, it was held in Telescope Mount T90 on the right side of the gun cradle. The telescope design included front and rear mounting collars, a locking pin, focusing nut, diopter scale, eye shield, and windows for illuminating the reticle. After the telescope was aligned with the gun bore, the gunner looked through the sight with the eye about 1 1/4 inches from the eye lens and used the turret and elevation controls to place the target at the correct point on the reticle.
The standard M71C reticle was marked “90-M82” and carried part number 7672267. It was calculated for the 90mm Gun M3 firing the M82 armor-piercing capped projectile at a stated muzzle velocity of 2,670 feet per second. The central cross indicated zero range and zero deflection. Range markings extended from 400 through 4,600 yards, while horizontal divisions provided 5-mil lead or deflection references. A descending broken line allowed for projectile drift and lateral jump. An external instrument light could shine through the illumination windows for night or low-light aiming.
- Official designation: Telescope M71C
- Stock number: 7578170
- Serial number: 9042
- Magnification: 5×
- Field of view: 13 degrees
- Primary weapon: 90mm Gun M3
- Documented tank application: T26E3/M26 Pershing
- Later listed applications: M36, M36B1, and M36B2
Weapon System History
The 90mm Gun M3 was adapted from the Army’s 90mm antiaircraft-gun family for installation in armored fighting vehicles. It gave American crews greater armor penetration and a heavier high-explosive projectile than the 75mm and 76mm tank guns then in widespread service. The M36 gun motor carriage combined the 90mm M3 with an open-topped tank-destroyer turret and reached combat units in Western Europe during 1944. The T26E3 combined the same gun with heavier armor and a fully enclosed turret. A small number of T26E3 tanks entered combat in Germany during early 1945, and the vehicle was later standardized as the M26 Pershing. The M26 remained in service after World War II and saw further combat during the Korean War.
History of Use
The M71C gave the gunner a magnified and mechanically aligned view along the path of the main gun. During a direct-fire engagement, the crew estimated the target range, selected the matching range and deflection point on the reticle, and moved the gun until the target appeared at that point. This method was used when engaging tanks, fortified positions, gun emplacements, vehicles, and other point targets. The 1944 technical manual documents the M71C with the T26-series installation, while wartime Ordnance material confirms its use on the T26E3. The later M36-series listing identifies the M71C as an alternative sight and should not be read as proof that every M36-family vehicle carried this model. The original vehicle assignment and service history of Serial No. 9042 are unknown.
Ideal For
This M71C offers a documented connection to the 90mm Gun M3 and two important families of American armored fighting vehicles. Its readable model, stock number, and serial number make it suitable for a historically accurate display, vehicle restoration, museum exhibit, or military-optics collection. The telescope also provides a useful example of the optical and mechanical fire-control equipment used before electronic tank sights and laser rangefinders became standard.
- T26E3 or M26 Pershing displays
- M36-series tank-destroyer projects
- 90mm Gun M3 exhibits
- World War II armored-vehicle collections
- Military optical-instrument displays
- Museum and educational exhibits
Approx length 27", Approx width 3", Approx height 3", Approx weight 12.6lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item’s general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
Please visit our page about order lead times here: Order Lead Times.