I'm asking this question because I am currently playing Hearts of Iron IV. It starts on 1/1 1936, and the Soviets have a big army of 1,1 million men but lack a lot of equipment. Some divisions are fine, but a big majority have only enough infantry equipment for about 10-20% of the men. Is this accurate?
I would say there was a lack of (modern) equipment in 1936, but not as much as indicated in your question.
By the mid 1930s the Red Army was the largest army in the world and was just as well equipped as any other army of the day.
The purges of the Red Army Officer Corps (1937-38) virtually destroyed Soviet military capability though.
The pre-war Red Army was at its greatest strength in the years preceding the purges. In the Constitution of 1936, Stalin proclaimed “Universal military service is law. Military service in the Workers' and Peasants' Red Army is a honourable duty of the citizens of the U.S.S.R.”.
This led to a ten percent increase of recruits for the following year and a higher standard of officer candidates. The estimated manpower was over 1.5 million active duty soldiers and 2.5 million reservists. The number of infantry divisions increased to 100, Soviet factories produced over 9,000 tanks, and the Red Army fielded over 6,000 pieces of artillery.
The airborne infantry consisted of over 70,000 trained paratroopers, with half a million possible reserves. The elite Red Air Force boasted over 10,000 aircraft and 16,000 highly trained pilots. The Red Navy, which had languished from neglect after the Kronstadt uprising, also began to develop strength in the early 1930s. By April 1936, naval planners had worked out a force structure to be completed by 1947 consisting of 15 battleships, 22 heavy cruisers, 31 light cruisers, 162 destroyers and destroyer leaders, 412 sub-marines and many support vessels.
In 1936, the Red Army proudly demonstrated its military capability to foreign guests in a massive military exercise that involved over 1,200 paratroopers, 5,000 airborne infantrymen, and enormous quantities of vehicles, weapons, and ammunition dropped to ground forces via aircraft.
sources:
Michael Garder - A History of the Soviet Army
Edgar O’Ballance - The Red Army: A Short History
David Glantz - Stumbling Colossus: The Red Army on the Eve of World War
David Glantz - When Titans Clashed: How the Red Army Stopped Hitler
^^edited ^^for ^^accuracy
I couldn't find any figures for 1936, but here is data for 1938, which shouldn't be radically different. Total amount of men in rifle formations: 616,000, cavalry: 95,690, armoured forces: 90,880, artillery (not including artillerymen from infantry units): 34,160, 370 chemists, 11,120 in automotive units (including Mongolian).
Total amount of Mosin 91/30 rifles produced in 1938: 1,124,664. Obviously, a lot of these people wouldn't be using rifles in their day-to-day fighting, but it's quite clear that there was no shortage in basic infantry weapons.
Sources:
http://www.battlefield.ru/plan-to-reorganize-red-army-1938-1942.html
I. Karachov, Russkaya Vintovka