The Future of Tanks

"Theses of the report by the commander of the Armoured and Mechanized Forces in the Group of Soviet Forces in Germany, Marshal of the Armoured Forces Rotmistrov, titled "Tanks of the Soviet and Foreign Armies Presently, and the Potential of Their Development"

March 24th, 1947

Overall conclusions regarding the tanks of WWII and the potential of its development:

1. Due to the thickening of armour and gun calibers, light tanks are departing from the battlefield. The amount of medium and heavy tanks is increasing.

Devourer of Tungsten

In late summer of 1942, the Red Army captured a German weapon that piqued the interest of the Red Army Main Artillery Directorate. This was the new German tapered bore 7.5 cm Pak 41. Several shells were captured along with the gun, which allowed trials to be performed and several characteristics to be determined. What was this gun, and what were the results of its trials in the USSR?

German SPG Intel

"Information notice #34

Information on enemy armameng

1. German 42 mm anti-tank gun mod. 1941

According to information obtained from various sources, the Germans use a 42 mm anti-tank gun mod. 1941 

World of Tanks: Today in History: Conical Barrels

On July 13th, 1940, a series of trials of the 2.8 cm schwere Panzerbuchse 41 anti-tank gun began at the Kummersdorf proving grounds in Germany. This was the first ever application of a conical barrel in artillery.

The principle of a conical barrel and a bullet for it were developed by a German gunsmith Karl Puff between 1903 and 1907. In 1920, another German engineer, Hermann Gerlich, refined the design.

The conical barrel's diameter next to the breech is larger than the diameter at the muzzle. A shell used in a conical barrel has special guiding bands that compress as the barrel width decreases. Because of this, the expanding gases act on the shell optimally throughout its presence in the barrel, and their energy is most efficiently used. The muzzle velocity of a shell of bullet released from a conical barrel is much greater than one released from a regular barrel. This increases penetration, and allows the use of a lighter shell.

Initially, conical barrels were only used in small arms. In 1930, Gerlich was testing a rifle he designed with a muzzle velocity of 1700 m/s. From 50 meters, it effortlessly penetrated a 12 mm armoured plate. In 1932, Gerlich, having emigrated to the United States, proposed his new rifle to the US Army. Its bullets were fired at a speed of 1800 m/s, a record that stands to this day. The rifle did not make it into production due to high cost and complexity.

The use of conical barrels in artillery became possible when it could be established that a shell retains sufficient stability in the cylindrical rifled section of the barrel, after which it can be compressed in a conical section. Due to this discovery, the conical section of the barrel could become smoothbore, which made the gun simpler to produce. Guns with conical barrels were used in the German army and had very high technical qualities.

In the USSR, work on a conical gun began before the Great Patriotic War, but Soviet engineers were unsuccessful. After studying captured German weapons, Soviet engineer Grabin created a light anti-tank S-40 gun, using the German 7.5 cm PaK 41 as a prototype. Grabin's gun had superior ballistics and penetration compared to the German gun, and was capable of penetrating any enemy tank at any combat distance at the time.

Original article available here.

PaK 41 Squeezebore Gun

In August 1942, Soviet successes in the Rzhev direction led to the capture of a number of trophies, including a PaK 41 squeezebore gun. On October 29th, it was tested in the Gorohovets artillery proving grounds. Only 3 shells were captured, however, so the results are somewhat limited.

CAMD RF 81-12038-54

"Due to a lack of homogenous armour plates 120 mm thick at the Gorohovets artillery proving grounds, it was decided to shoot at two plates: 45 mm and 100 mm angled at 30 degrees from normal. Both plates were mounted on a wooden frame and attached with metal bolts. 100 mm plate [illegible], the 45 mm plate was placed as close as possible. Due to deformations of the 100 mm plate from previous tests, the space between the centers of the plates was about 30 mm. The plates were square, 1.2 meters per side. Shots were fired directly. The gun elevation was set with a quadrant.

The first shot was fired at  200 meters. The shot missed, and it was decided to shoot from 100 meters. The second shot hit the wooden frame. 

The third shot was fired from 75 meters. On impact with the armour plates, the ballistic cap was deformed, and the core shattered into small pieces. The jacket was deformed and got stuck between the 45 mm plate and the 100 mm plate."