I plan on ordering a Vepr in 7.62x54r tonight and before I decided on that I was looking at a PSL and I kept reading to only shoot 147gr or lighter ammo, but could never find a reason why? If thats an actual thing, why is it? Is it the same with the Vepr? I have lots of HB (182gr) surplus ammo and don't want to tear anything up, but I also have lots of 147gr to shoot if thats not safe. Can anyone confirm this?