Hey everybody, I started mearsuring my 142 grn MK'S today with my new Bearing Surface Comparator. This is what I found so far. I conducted a test on 200 bullets. I found my zero point (.000)and started the test. Most of these bullets (160) measured between .002 from each other. There were some(40) that measured .004 and .005 from the group that fell into the zero to .002 range. I think I am doing this right. WHAT IS AN ACCEPTABLE DIFFERENCE, IN MEASUREMENT, BETWEEN EACH BULLET. I know I am supposed to be looking for the bullets that have the same bearing surface, or close to the same. I need help with this process, I am new at doing this and want to make sure I am doing it right. Thanks guys, Wildcat.