August 11th, 1941
To the Chief of Artillery of the 19th Army
Practice shows that firing 76 mm HE shells with a delayed fuse is ineffective.
Better results are obtained when firing 76 mm HE shells with an impact fuse. Shooting like this can ruin the suspension, destroy armament, and knock out the crew.
In the future, when firing at armoured cars and light tanks from a 76 mm gun at an angle of less than 30 degrees, set the fuse to high explosive action. At the same targets at an angle of 30 degrees or more or medium and heavy tanks, set the fuse to fragmentation action.
When firing 85 mm HE shells from mod. 1931 guns consider that they can penetrate 45 mm of armour at 30 degrees from 500 meters, and 50 mm of armour under the same conditions can be penetrated from 300 meters or closer.
Deliver the above information down to the gun commanders.
Acting Chief of Artillery of the Western Front, Major-General of Artillery, Kamera
Commissar of Artillery of the Western Front, Regimental Commissar"
It appears that there is a mistake in the document: the mod. 1931 AA gun used 76 mm ammunition, not 85 mm. Both types of gun were used extensively in the anti-tank role in 1941 due to a lack of dedicated anti-tank artillery. In 1943, both guns served as the base for tank guns (the 85 mm D-5 and 76 mm S-54) since their AP ballistics were superior to the T-34's F-34 gun. However, the F-34 proved it capable of penetrating a PzIV's armour at any range with HE, so perhaps the slower muzzle velocity resulted in more reliable detonation.