You are right Mike that bullets seated well back from the rifling will often not perform as well as those seated closer. But I've done a lot of study and chambered a lot of rifles, and feel it's more than that. The faster twists definitely favor longer bullets. For instance, in all the 7mm rifles, (7x57, 7-08, 280) exc the 7 mag (which I never liked), I preferred the Shilen 1/11 twist barrels. using the same reamer (throat etc) they consistently shot better with bullets under 160 gr. and about as good with the 160's. The fast 1:9 twist did a little better with the 175's. Some of the 6.5X57's have twists that I've measured around 1:8. And yes they all have the long throat to accomodate those long heavy round nose bullets. Some of them do shoot very well though, especially when you slow it down a notch. After all stability is a facor of RPM's, not velocity
. I've had some sub MOA 6.5's and recommended them to my customers over the years. A favorite wildcat was the old 6.5 "souper" or 6.5/308 in a 1:10 twist bbl. There was a pretty good calculator we used years ago, but can't seem to find my copy or even recall who the author or engineer was who designed it, but it proved to be reliable. Some of the manufacturers should have paid attm to it. I recally the 32 Win spl, was borderline and the accuracy usually showed it.

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