I've mentioned some of this in the [distant] past, but it may be worth repeating. The 6.5mm, 130gr. "kurtz" (Buckshot's name for it) group buy has produced outstanding results in my "as issued" Carl Gustaffson Swedish Mauser...if I do everything correctly. That means sizing the CB's nose first, adding a GC and then sizing & lubing again @ .267". (My rifle doesn't like .266" CB's very much, which makes it a bit of an oddball.) The alloy is WW with perhaps 1% Sn added, but with no heat treatment. I use light charges of powders like WC 820 (16gr.), VV N133 (18 - 19gr.), AA 5744 (17 - 19gr.) or H/IMR 4198 (17 - 19gr.) with standard LR primers to hold the velocity to a modest level due to the fast twist of the rifling. Accuracy has been as good as 10 in 1" @ 50yds. from a rest when the planets are in alignment and I'm paying attention.