ZIS-5, Take One

"May 30th, 1941
To the Central Committee of the VKP(b)
Comrade Zhdanov

According to USSR SNK and Central Committee Decree #1216-502 issued on May 5th, 1941, two experimental T-44 tanks built by factory #183 are supporsed to be armed with the 76 mm ZIS-5 or 57 mm ZIS-4 gun. The main characteristics of these guns is shown in the following table:

Gun model	Caliber in mm	Muzzle velocity, m/s	Shell mass, kg	Penetrates armour
				At 0 degrees		At 30 degrees
				Thickness in mm	Distance in m	Thickness in mm	Distance in m
F-34	76.2	662	6.3	60	Up to 1000	50	Up to 1000
ZIS-5	76.2	813	6.5	90	Up to 1000	70	Up to 1000
ZIS-4	57	992	3.14	90	Up to 1000	70	Up to 1000

The penetration of the ZIS-5 and ZIS-4 is equivalent. Since the ZIS-5 HE shell weighs more than the ZIS-4 shell, its explosive action is significantly better. The F-34 gun's HE shell is equivalent to the ZIS-5, but the F-34 has lower penetration.

Despite this, arming the T-44 with the ZIS-5 76 mm gun is unreasonable because:

1. The ZIS-5 is not in production. Factory #95 built one prototype to install in the KV tank.
2. The 76 mm ZIS-5 gun was designed to use the shells of the 76 mm 3-K gun. The 76 mm 3-K gun has been out of production since July of 1940 and is still only used at the corps level.
   As such, supplying T-44 tanks with ammunition would be very difficult, as supplies would have to go from the corps.
3. Various types of guns (F-34, ZIS-4, ZIS-5) will make it difficult to train crewmen, and supply the guns with parts, tools, and ammunition.

Keeping this in mind, I report that the decree of the USSR SNK and Central Committee regarding the armament of the T-44 must be altered in the following manner:

"Arm one experimental prototype of the T-44 with the 57 mm ZIS-4 tank gun, and one prototype with the 76 mm F-34 tank gun".

The machineguns and ammunition must be left as they were.

Marshall of the Soviet Union, Kulik

GABTU Chief, Lieutenant-General of the Tank Forces, Fedorenko"

CAMD RF 38-11355-10