Roskoe

I agree with B.C. - there is only so much research you can do on this stuff before you have to just go out and spend some time at the bench . . . and then some more time at the range. Every one of these guns is it's own little DNA molecule. Some have shorter throats - some longer. Some develop high pressure with 57 grains of IMR 4357 - some digest these loads all day without a squabble. Some shoot a lot of different bullets well. Some only shoot one load. Some don't shoot anything worth a hoot. Not that research is a total waste of time, but get out there an pay your dues like the rest of us.

BFR

Going back to the original question, how old is the brass? A looser fit in the primer socket will send the primer back to the bolt more easily, causing it to flatten more. I've found that most of my older brass ejects with flattened primers, even with moderate loads. food for thought.

haugenna

BC and Roskoe,thanks for the help, just so there is no confusion, I am aware that each rifle is different,but I am looking at a huge difference 3.357 is the longest I can get a cartridge to fit in the Tikka's detachable magazine. When I checked the lands on my cartridge, it came to 3.520 so I was well off the lands when I shot these loads...but to answer your other questions bc, there were no other signs of high pressure. So I will continue incrementally until I see other pressure signs. Ok lets put this post to bed.

Haugenna