"Tactical-technical requirements for a project and experimental prototype of two 23 mm MP-6 guns paired with a 7.62 mm model 1940 (DS) machinegun and AA automatic sight, mounted in a T-34 turret.
Two 23 mm automatic MP-6 cannons and a 7.62 mm model 1940 (DS) machinegun are installed in a T-34 for the purpose of anti-aircraft defense of tank forces and combat in mountainous conditions."
Some more details on the gun:
"As a result of your request #145664 from April 22nd 1941, blueprints for the 23 mm automatic MP-6 gun were sent by OKB-16
- magazine fed (for use in tanks)
- belt fed (for use in aircraft).
To factory #183 (Comintern) by #10-336 on April 24th, 1941
To factory #174 (Voroshilov) by #10-337 on April 24th, 1941
To factory #37 (Ordzhonikidze) by #10-338 on April 24th, 1941"
The tank version of the MP-6 gun was called the PT-23TB (Gun, Tank, 23 mm, Taubin-Baburin), and was also intended to replace the 12.7 mm machinegun on the T-40 tank.
There was another AA T-34 project, this time with four 37 mm guns.
"Addendum to tactical-technical requirements of an experimental prototype of a quad AA mount on the chassis of a T-34 tank
- The quad 37 mm AA mount is placed in a special turret, mounted on a T-34 hull.
- The combat weight of this vehicle should not be greater than that of a T-34 tank.
- The crew consists of 8 people (6 person gun crew, mechanic-driver, radio operator/machinegunner).
- The turret should protect the crew from fragments of bombs and small caliber shells (antitank rifles, aircraft autocannons, etc).
- The gun arc should have the following ranges:
- Vertical: -5 to 85 degrees.
- Horizontal: 360 degrees
- The aiming speed should be the same as on the regular quad 37 mm AA mount (produced according to the technical characteristics defined by GAU KA).
- The average rate of fire per barrel should be no less than 60 RPM.
- The vehicle should be able to fire while stationary or on the move.
- The vehicle should be able to cover a distance of 500 km with an unlocked gun mount.
- The sights should support fire on ground and air targets at a distance of up to 3000 meters.
- The mobility characteristics of the vehicle should be identical to those of a T-34.
- The roof of the turret should consist of removable armour plates that protect the crew from bullets and infantry mortars.
- The presence of a roof should not impede the observation of the commander or gun crew. A commander's cupola with tilted vision blocks will be used for observation of ground targets.
- The turret should comfortably contain the crew and at least 400 rounds of ammunition. The rest of the ammunition should be stored in the hull.
- Ejected casings should be caught by a case catcher with the capacity for 600 cases. The case catcher should be capable of being emptied rapidly.
- The commander should have contact with the driver via light communication device.
- External communication is achieved with a stock radio.
- A container for storing the crew's possession should be included.
- Two SMGs should be placed in the turret, with ammunition.
- The technical project will be reviewed by GBTU and Artkom.
These technical-tactical requirements are preliminary and may be revised throughout the design process.
GBTU USA Chief, Major-General of the Tank Engineering Service, Alymov
GBTU USA 4th Department Chief, Engineer-Colonel Korolev
November 19th, 1945"