The SU-100 presented in the museum was a medium-weight self-propelled artillery gun. It belonged to the class of tank destroyers. It entered service with the Red Army by Resolution of the State Defense Committee No. 6131 dated July 3, 1944.
The new self-propelled gun was developed on the basis of the chassis, main components and assemblies of the T-34-85 tank and the SU-85 self-propelled gun. When designing the SU-100, 72% of the parts were borrowed from the T-34-85 medium tank, 7.5% — from the SU-85, and 4% — from the SU-122. Only 16.5% of all parts of the new self-propelled gun were designed specifically for it. Most of these parts and assemblies were needed for the mechanisms of installation and attachment of the gun.
The engine, transmission, and chassis, which were borrowed from the SU-85, remained virtually unchanged. At the same time, the hull underwent some significant transformations. First of all, the thickness of the front armor was significantly increased — from 45 to 75 millimeters. To ensure a better view of the battlefield, the self-propelled gun was equipped with MK-IV type observation devices, and the commander’s cupola was installed on the roof. For the most optimal cleaning of the crew compartment from powder gasses, two special fans were installed in it.
The SU-100 had a classic design. The conning tower was located in the front of the hull. In the conning tower there was a crew compartment combined with a control compartment. It housed the breech of the gun with sighting equipment and accessories, a radio station, an intercom, ammunition, front fuel tanks, a set of tools and spare parts.
Immediately behind the fighting compartment was the engine. The aft part of the hull housed the transmission compartment. The main and significant difference between the SU-100 and the SU-85 and SU-85M was the gun. The SU-100 was fitted with a rifled 100-mm D-10S tank gun of the 1944 model with a 56-caliber barrel. The total weight of the gun was 1,435 kilograms, and the maximum length of recoil when fired reached 570 millimeters. The gun was equipped with a TSh-19 telescopic folding sight for direct fire.
For shooting from closed positions, there was a longitudinal level and a Goerz panorama sight. From the outside, the attachment point of the gun was protected by a movable armored mask of spherical shape. The ammunition load carried by the gun included 33 fixed rounds.
