No, no, no The base diameter on those cartridges is 12.01mm or .473", much smaller than your chamber 12.3 or .484", a 6.5x57 is even smaller at 11.9mm or .469",this is what makes me believe you have an over polished chamber.
Your issue is the diameter of your chamber at the base and at the point of the bulge is larger than your brass by more than tolerances allow. Some of the brass when pushed this far is failing. I converted the measurement in MM to inch and can not find any cartridge to match. Do you have a micrometer that measures in inches? The chamber should only be a couple of thousandths of an inch larger than your brass. As mentioned above, this is very dangerous.
Last edited by SKB; 12/30/19 03:06 PM.
