DB,
I tried some in my .280 Rem and got groups under .5" at 100 yards (three shots); best was .444". I just picked an LOA and loaded them up with H4831.
I have a pair of rifles in 6.5-'06 and the .280 built by the same gunsmith both with Red Elliot reamers. I have been shooting the .264"/.130 gr VLD and used the same distance from the lands as the 6.5 for the .280. I guess it worked.
jim