by Hoot » Thu Dec 14, 2017 7:19 pm
Jared, QL tends to over-predict a little to keep the overambitious from harm. Not by much though. Obviously, no one in their right mind starts testing at max load. AA 1680 has been a relatively safe powder given its volume versus energy content. Another powder to consider, but hich is also not characterized by QL is the new Hodgdon CFE Black.With all due respect to the AR10 platform, I would not set the maximum chamber at 65k. Maybe in a bolt gun. There's always time to work up but rarely to work down when you've gone too far. I used QL to establish starting points for both .308 and 260 Rem in an AR10 platform, but not a straight walled cartridge that is not SAAMI approved. You'll be sailing in relatively uncharted waters, save for the load reports from folks like Kiwi Greg. No disrespect to Wildcatter, but take his load limits with a healthy dose of caution. By his own admission, he never worried about the cost of blowing up guns. We mere mortals, aka working stiffs, see life through different glasses. In theory, (see sig) either W296 or H110 would be good matchups for a 250gr bullet since they are well suited in the 450 LM's little brother. That being said, some powders behave differently at higher pressures, so the recipe that works for the 450b may not scale linearly upward just because the 450 LM case holds xx grains more powder.
I am not at all comfortable giving advice on a caliber that I've never loaded myself. If you don't mind, I'll be content to just watch you guys forge new trails. I've never created new calibers using QL, so I'm no authority as to how that'll go.
Hoot
In Theory, there is no difference between theory and practice. In Practice, there is.