SU-152 "Taran"

SU-152 "Taran" (СУ-152 "Таран") was a fully enclosed Soviet tank destroyer built in 1965, that never progressed past the experimental stage.

History
In the early 1960s the Soviet military concluded that the armor-piercing ammunition used by the T-54 and T-55 medium tanks, and the T-10 and T-10M heavy tanks was unable to penetrate the frontal armor of the newest American M60 and British Chieftain main battle tanks. The Soviets therefore began parallel research on several different anti-tank weapon systems: development of new APDS and shaped charge ammunition for existing tank guns, new rifled and smoothbore tank guns with a caliber of 115–130 mm and anti-tank missiles among others.

One of these projects became the SU-152 "Taran". The factory designation was Object 120 (Объект 120). In terms of firepower and mobility it surpassed all foreign tank destroyers. It was similar to the British FV 4005 Stage 2 that was developed in July 1955 and that was armed with a large 183 mm gun. The main reason SU-152 "Taran" wasn't adopted was the development of effective 125 mm smoothbore tank guns and anti-tank missiles.

Armament
The SU-152 "Taran" was armed with the 152.4 mm M-69 "Taran" rifled gun, with a barrel length of 9045 mm, fitted with a powerful muzzle brake. With an overall length of about 10 meters it is probably the longest gun of any type ever installed in a fully enclosed armoured fighting vehicle. The gun had a maximum direct fire range of 2050 meters. The SU-152 "Taran" carried 22 rounds of APDS and high-explosive ammunition. The gun had a semi-automatic breech block, with a rate of fire of 3–5 rounds/min. The high-explosive ammunition had a 43.5 kg shell and a maximum charge of 10.7 kg. Firing the 12.5 kg APDS shell with a maximum charge (10.7 kg), which gave it a muzzle velocity of 1720 m/s, the M-69 "Taran" had an armor penetration of 290 mm of RHA at 90° at a range of 2000 meters.