Here is an article that compares USSR, German and Lend Lease production of various items by year. Apparently, most of the USSR ammo factories were overrun in the first year of the war. But for Lend Lease, the Soviets would have had a critical ammo shortage.
But the author concludes that Lend Lease only shortened the war, it did not affect the outcome.
An Examination of Soviet Armaments Factories and Their Production
But the author concludes that Lend Lease only shortened the war, it did not affect the outcome.
An Examination of Soviet Armaments Factories and Their Production
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