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Are any of you measuring bullet diameter (maybe to +/- .0001") to see if there is a corelation to the length measurements
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Yes. On a few of those longer ones, there are high sides that make the diameter slightly larger but that has only been the case with the 300 grain .338 MK. All other bullets seem to be better.
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At the very least this measurement should increase or decrease drag on the bore within a given BS length. Yes? No?
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Yes it does. On our 2000 yard shooting, bullets that were segregated according to bearing surface length made the standard deviations get reduced by half and the vertical stringing at 2000 yards was reduced more than just trimming meplats alone. In fact, the last time we tested the MOAG at 2k on our hunting trip, NONE of those bullets had been trimmed, but all were segregated by bearing surface. In the grand scheme of things, I would say that bs segregating makes 98% of the vertical stringing disappear, and meplat trimming makes up the remaining 2%!
One thing I would also like to mention is that most of this extra technical stuff really means nothing if you are just shooting out to 1000 yards or less. Maybe even 1500 yards or less. I never do any of this crap to my other guns, and they shoot great at and up to 1500. Of course, they are using smaller bullets that are easier to make consistent than that big 300 grainer. I have 600 140 grain 6.5mm Berger vld's for "old blue" right now, and they have meplats that are perfectly flat right from Berger, and the bs and ogives on them vary less than .001"!
In other words, on a .308 that goes subsonic at 900 yards or maybe 1000, and is just being used for varmints and gongs and not comp, I would just forget about all this tech crap. Just load them up with <font color="blue">normal </font> match techniques and go shoot. It is kindof like trying to super tune a toyota camry to run the quarter mile in 11 seconds by just changing the air filter. It ain't gonna do you much good. Better off just getting a tricked out muscle car. /ubbthreads/images/graemlins/wink.gif