Uralmash-1

The Uralmash-1 (Уралмаш-1) was a Soviet prototype self-propelled gun developed during World War II. It was a turretless, tracked armoured fighting vehicle designed by the Yekaterinburg-based Uralmash design bureau (UZTM) between autumn 1944 and spring 1945. It used the chassis of the T-44 medium tank and was intended to replace the SU-100 which itself had only entered service with the Red Army in late 1944. Two prototypes of the Uralmash-1 with different armament were built in early 1945, one with the 100 mm D-10 tank gun, the other with the 122 mm D-25S tank gun. While mass production was initially recommended, the end of the war with Germany in May 1945 eventually caused the project to be cancelled due to lack of necessity. If the Uralmash-1 had entered service, the 100 mm variant would have been designated SU-101 (СУ-101) while the 122 mm variant would have been designated SU-102 (СУ-102), in accordance with Soviet military nomenclature, where the "SU"-label stood for Samokhodnaya Ustanovka, or self-propelled gun.

==Development history== thumb|left|SU-101 and SU-100 Work on the SU-101 and SU-102 at the Uralmash design bureau had basically started parallel to the creation of the SU-100, in summer 1944. While the latter, based on the chassis of the T-34 medium tank, proved satisfactorily in combat, its basic layout with crew compartment in the front and engine in the back was considered a flaw. The lowly mounted gun protruded far from the vehicle's front, which resulted in cumbersome maneuverability in urban or forested areas and could cause problems in undulating terrain, where the vehicle could potentially ram its own muzzle into the ground if not driven carefully. Additionally, the SU-100 was very front heavy, which resulted in excessive stress on the forward road wheels, risking mechanical failure. Should the need for upgrading the vehicle with a bigger and heavier gun arise, all these problems were expected to be massively exacerbated.