"Report on the actions of 122 mm howitzer model 1938 armour burning ammunition
Batteries of the 77th Howitzer Artillery Brigade used armour burning ammunition against enemy tanks near Gorodisk on August 30th, 1944 (305th Howitzer Artillery Regiment) and near height 107.5 o the Narva beachhead on October 4th, 1944 (229th Howitzer Artillery Regiment).
The best range of firing HEAT rounds is 400-600 meters. At 500 meters the armour of a German Tiger tank can be penetrated. At a range of over 600 meters the round ricochets and cannot penetrate the front hull or turret armour. If the turret is hit it becomes jammed and the tank is disabled.
The side armour can be penetrated at a range of up to 800 meters if the impact angle is small.
At a range of over 1000 meters the fire is effective only to destroy tracks or armament. The track is destroyed if hit at a range of up to 1200 meters.
Firing at a range of over 1000 meters at a Tiger tank is ineffective. There were cases where one gun firing from 150-200 meters burned up a Tiger with a hit to the side. There was also an instance of a tank being burned by the 229th Howitzer Artillery Regiment by hitting it in the engine (rear).
The front of a medium tank can be penetrated from a range of 800-900 meters. When firing at an APC it can be disabled with a hit from any distance.
Indirect fire at enemy tanks with HEAT ammunition was ineffective. HEAT was not used to fire at fortifications.
Chief of Staff of the 77th Howitzer Artillery Brigade, Lieutenant Colonel Naryshkin
1st Assistant to the Chief of Staff , Guards Major Popko
November 2nd, 1944"