Don't forget that those are ex US Lend Lease guns sent in WW2 to the Soviet Union, who had little reason to put them to use. They took American fighter planes, GMC trucks, Sherman and Grant tanks, and Valentine tanks and No.19 Radio Sets from Canada. That equipment was never destroyed after the end of the war, because someone calculated it might help Mother Russia in the hands of a Freedom Fighter. The Viet Cong and North Vietnamese received lots of ex WW2 German and American arms as lethal aid. The fact it still is in one place in a former Soviet republic is more surprising to me.