I'm entering a new world here. Gearing up to do some really long range predator hunting. Tho't I otta start now in learning to prep loads. Rube Goldburg'd a Bearing Surface length measurement device. It's kinds sweet. Here's what I found after weighing and measuring the bearing surface length of each of the 19 bullets I have remaining from a lot. 1)Bearing surface length and bullet weight vari pretty much identically. That is, the heavier bullets have longer bearing surfaces. They sort in perfect order that is, in every case the next lighter bullet has the next shorter BS. 2)If I toss the 3 heaviest and 4 lightest bullets, weight of the remaining 12 bullets is +/- 1.0 grain of design weight. 3) If I toss the same 7 bullets as above, the longest BS is 0.438" and the shortest is 0.429" 4) Average BS is 0.432" the largest group with the same BS is 5 bullets with 0.434" 5) Did the same test on some 250gr SMKs and there wasn't enough variance to mess with. They were all pretty much spot on. This is an elk rifle that I'm messing with with a max limit of 820 yds (that's where the bullet is 5 mils low, no more mil dots and with me shooting it the limit will be 550yds or less, cause that's my comfort zone limit. So I don't think this level of detail makes a hoot of difference at those distances. I just want to be sure that I'm heading in the right direction when I start getting serious on truly longrange stuff. BTW, the box that I got the 19 bullets from consistently outshoot the SMKs by better than 50% that is, SMKs run just a bit better than MOA and these things run around half MOA and they were random picks from the box when loading.