The Russian Civil War left the Soviet armaments industry in poor condition. The existing Tsarist factories were overhauled, but little was done in the way of modernization or expansion until Stalin began his program of industrialization. New factories were built, often with German or American machinery, and existing ones were modernized. Most of the new facilities were located near the Volga or even further east in the Urals, but this was generally true more for the artillery plants than the tank and automotive factories, which were often converted to armaments production from Tsarist heavy machinery plants west of the Volga.

Sources

Harrison, Mark. Soviet Planning in Peace and War, 1938-1945. Cambridge: Cambridge University Press, 1985
Sharp, Charles C. Soviet Order of Battle, World War II, Volume III, "Red Storm", Soviet Mechanized Corps and Guards Armored Units, 1942 to 1945. West Chester, Ohio: George F. Nafziger. 1995.
Sokolov, Boris. "The Role of Lend-Lease in Soviet Military Efforts, 1941­1945". Journal of Slavic Military Studies, Vol. 7, Nr. 3, 1994.
Volz, Arthur G. "Soviet Artillery Weapons, Part 2", Soviet Armed Forces Review Annual, Vol. 11, 1987-88, Gulf Breeze, FL: Academic International Press, 1989.
Volz, Arthur G. "Soviet Artillery Weapons, Part 3", Soviet Armed Forces Review Annual, Vol. 12, 1988, Gulf Breeze, FL: Academic International Press, 1993.
Zaloga, Steven and Grandsen, James. Soviet Tanks and Combat Vehicles of World War Two. London: Arms and Armor Press, 1984.

More Soviet Armaments Factories

Introduction
Tube Artillery
Lend Lease Artillery, Mortars, and Rocket Artillery
Ammunition, Lend Lease Ammunition and Explosives
Armor, Armored Fighting Vehicles and Tank Factories
Lend Lease Armored Fighting Vehicles and Motor Transport
Soviet Factories and Europa