Hi! I got a Mosin 91/30, Soviet production, captured and re-worked by the Finns. It shoots pretty good and well. I had such a trouble shooting original (Russian) Barnaul ammo for hunting. After 14 shots the chamber was very hot and I had to wait it was cold to open the bolt. Shooting military Barnaul ammo I hadn't such a heavy trouble anyway the bolt was/is not so "smooth". Never I had/have that trouble using ammo loaded at home...

well, now I load my ammo. Maybe the ammo you're firing are "over pressure" for your rifle. Be careful.