The combat experience of the initial period of the Great Patriotic War proved the necessity of accompanying tanks in battle with self-propelled artillery, and in October 1942 the State Defense Committee decided to begin work on the creation of not only light and medium, but also heavy self-propelled artillery (SPG). This self-propelled artillery was to be armed with a 152 mm ML-20 mod. 1937 howitzer and used in offensive operations to break through the enemy's fortified defenses. The Chelyabinsk Kirov Plant (ChKZ) was entrusted with the creation of the machine. The KV-14 belonged to the type of fully armored self-propelled units with a frontally-armored cabin and was created on the basis of the KV-1S tank.

The SU-152 (KV-14) was the hull of the KV-1S tank, whose control and fighting compartments were combined in a welded casemate. The crew consisted of five soldiers: the driver was located in the front left control compartment, behind him the gunner, behind the gunner the loader, to the right of the gun in front the commander of the vehicle and behind him the turret commander. For observation of the battlefield a PTK-4 periscope was used, which provided a panoramic view, and five prismatic mirrors were installed on the roof of the superstructure and on the covers of the left and rear hatches. There was an escape hatch in the right hatch cover.

In the engine compartment, a V-2K diesel engine was installed along the longitudinal axis of the fuselage, along with engine and transmission components and fuel tanks.

The armament of these self-propelled guns consisted of a 152 mm howitzer-gun, model 1937, ML-20S. The direct firing range of the gun was 3800 m and the maximum indirect firing range was 6.2 km. The following rounds were used for firing: OF-540 high-explosive long-range steel cannon shell (43.56 kg, 655 m/s), G-530 concrete-piercing howitzer shell, OF-530 high-explosive long-range steel howitzer shell, 0-530A cast-steel long-range fragmentation howitzer shell, B-540 armor-piercing tracer shell (48.78 kg) and high-explosive naval semi-armor-piercing shell with KTMF fuze. Loading was separate: charges for the new and old guns were used, and special charges were used for firing armor-piercing tracer shells (with an initial velocity of 600 m/s) and high-explosive naval semi-armor-piercing shells (with an initial velocity of 573 m/s).

A total of 670 SU-152s were produced. The self-propelled guns entered service with the heavy self-propelled regiments of the Stavka. SU-152s entered combat for the first time at the Kursk Bulge and despite the small number of available vehicles the effect of their use turned out to be very significant. It was then that the self-propelled gun received the respectful nickname "St. John's Wort": heavy armor-piercing shells penetrated the armor of any Wehrmacht tank at a distance of up to 1500 m. Even if the shell did not penetrate the armor of an enemy vehicle, it disabled it due to failure of components and mechanisms caused by concussion and injured the crew with fragments from internal armor splinters. Shooting at enemy equipment with high-explosive and concrete-piercing shells also gave good results (after all, the G-530 concrete-piercing shell penetrated reinforced concrete walls about 1 m thick).

SU-152s were used at the front until the summer of 1944, mainly as heavy antitank guns — then they were replaced by the new ISU-152 and ISU-122 heavy self-propelled guns.

Used sources:

1. M. Baryatinsky “Heavy self-propelled guns of the Red Army”, magazine “Armor Collection” No. 02 2006.

2. M. Svirin “Stalin’s self-propelled guns. History of Soviet self-propelled guns 1919-1945" 2008

3. G.L. Kholyavsky “Complete encyclopedia of tanks of the world 1915 - 2000” 1999