My dad's friend is selling his sporterized k98 Mauser. I'm about 98% sure we are getting it. I can't find anything online for it. The only numbers I found on the rifle was R-1858. It has a stamping under the front Weaver rail (two piece Weaver mount) but the rail pieces were either glued or soldered on. It says 7.92 on the side of the receiver, but I can't find any 7.92 ammo. I read online that there is 3 different 8x57 variations : 8x57, 8x57j, and 8x57js. I may be wrong on one of them. I measured the bore diameter : .3118. It has the original barrel on it. Which 8x57 ammo do I need for this rifle?