Re: Sierra 6.5mm 123 gr MK, why are we not using it???
Should do fine in an 8 twist. Its certainly more then needed but in the conventional chamberings, I would not think you would ever have a problem with bullet integrity issues because of excessive RPM levels.
Now something like a 6.5 RUM or 6.5 Allen Magnum, possibly but I would still suspect they would work fine. I have a 6.5 AM bench rifle with a 1-8 so I may give them a try just to see if we can rip them apart. We are hitting 3550 fps with the 142 gr so I would think possibly near 3800 fps would be reachable!!!
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