I've never seen a situation with long range competition stuff that such attention to detail is needed. As brand new unprepped cases holding powder charges with a 2/10ths grain spread can shoot bullets right out of the box into 15-shot groups at 1000 yards measuring under 5 inches (equal to or better than all the high dollar benchrest systems) from a low cost target rifle with a standard chamber, I consider all that micro-management of such details a total waste of time. But it does make the doers feel good and have confidence in their reloads.
Even loading a few thousand new cases with metered 3/10ths grain charge weight spread and bullet runout up to near .004" shooting 20 shots inside 3 inches at 600 yards in several rifles with different bore, groove and chamber dimensions; all without all that frivolous stuff done.
In my own tests, there's more spread across primer's output in a given lot of them than a charge difference of only one kernel (granule) of powder causes as far as muzzle velocity is concerned. So does a 10% change in case neck grip on bullets and few folks measure that at all.
The above aside, if you and yours do no worse than 4.5 inches at 1000, then maybe you're onto something.
