I've been hearing this a lot and seeing movies like enemy at the gates where one person had a rifle and the other got a clip of ammo, so when the guy with the rifle dies the other takes his rifle. How historically accurate is this? Considering how many mosins are out there and the fact that they are so cheap. Did the Russians really have a short supply of rifles?
Enemy at the Gates is a movie that magnified a couple of common misconceptions, in particular blocking detachments and armament shortages, about the Eastern Front and Stalingrad. Too bad we never got to see the original Enemy at the Gates, based not on Stalingrad but the Siege of Leningrad, with music from Shostakovich and directed by Sergio Leone. But, back to the topic at hand: since the movie is popular enough, your question has already appeared a number of times. One of the resident experts, u/Georgy_K_Zhukov, has answered it in great depth here: https://www.reddit.com/r/AskHistorians/comments/3pcjfv/one_gets_the_gun_the_other_gets_the_ammo_did_this/cw54qf3/?context=3
Edit: format, syntaxis and correct author citation.