I purchased a Mauser. On the tag it has " 91 Mauser and it supposed to shoot 7mm Mauser ammo. But I am not really sure if that's what it suppose to fire. Because it rifle looks alot like a Argentine Mauser that I once had and that took a diffent caliber, it was 9.65. Can you tell me more before I shoot the rifle. Iam somewhat afraid to fire it.