I have 2 different lot numbers of sierra matchKing 120gr .264 bullets . not measuring the over length of the bullet but the bearing surface . I expected a difference but not that much
Is that favoring in the boattail into the measurements? Like base of bullet to ogive? Or is it just the bearing surface? I have a few lots of Berger 156s from 5-6 years ago and the base to ogive on them is 20k shorter than the lots of I purchased 2 years ago. More variation than I expected there as well. They also lowered the advertised bc on the box on the newer ones.
Is that favoring in the boattail into the measurements? Like base of bullet to ogive? Or is it just the bearing surface? I have a few lots of Berger 156s from 5-6 years ago and the base to ogive on them is 20k shorter than the lots of I purchased 2 years ago. More variation than I expected there as well. They also lowered the advertised bc on the box on the newer ones.
I have shot a lot of sierra 107smk and 142smk. I typically buy the same lot, 2k bullets at a time. The largest base to ogive I've observed within same/consecutive lots was 0.003, however from 2k lot purchase to next, I've aboaerved up to near the same variation you're seeing here. I've also saw large lot to lot differences with the 115dtac 6mm bullet manufacturered by Sierra for David Tubb.
Talking with a custom bullet maker, I was told that the hardest thing to get consistent was the ogive.
A little more or less lube, slight difference in the jacket composition, slight difference in the stroke for sizing, can make a huge difference in measurements.
