Need some help figuring this out

[dougduey]

My guess is you found the combination of a "hard" bullet, at either "maximum" tolerance, or just over. Then fired it through a barrel either at "minimum" tolerances or under.

Hammer is the only mono's I will shoot, because Steve is the only person I've met willing to take material, and tolerances seriously.

HARPERC, I think you "hit the nail on the head"!! This makes total sense to me and would explain why I had no issues (with the same charge) with a few bullets yet problems with others.
Steve has made me a convert to the Hammer line of bullets. I love them and they are a work of art and total perfection. Every bullet is exactly the same. I don't have to bother measuring to the ogive with the Hammer bullets and can use the COAL measurement because they DO NOT VARY AT ALL!!