[nightdriver]

"I have personally experimented with my Omark single shot, heavy barrel target rifle, which has a Weaver 8 power scope fitted. Using 150 grain Sierra MatchKing HPBTs, IMR-4064 powder...."

What caliber were you using? .308? 30-06? 300 mag?

I'm thinking it was a 30-06. The .308 was brought out to provide a shorter throw in the action which reduced the weight, but 30-06 equivalent ballistics are not possible with IMR 4064, due to the smaller powder capacity of the .308.

The .308's ballistics required the use of the more dense filling made possible by using the ball powders, which can be a little tricky up in the maximun load range.

[ghostcat]

wish I could answer that but I'm not the author, just the poster ;^)