When you are achieveng a certain velocity with a given powder, and pressure signs start to indicate you are approaching the "excessive" level, you will NEVER get higher velocities at lower pressures with a FASTER POWDER! This is true regardless of barrel length!

The ONLY thing you can try is a slower powder, and you may not ever achieve any higher velocity regardless of what you try. You might, but you might not, either!

Well...

Found part of the problem (maybe)... operator error during reloading Apparently after checking the chamber overall length (COL) w/ the Stoney Point tool, I neglected to re-adjust the Forster Ultra seater from where it had been set for soft-seating 142gr SMKs into the lands. Now, w/ case necks set to a lot more neck tension... a 123gr Scenar touches the lands at 2.341", these were seated to 2.359" (ouch!). Think I found part of the reason for popping the primers... sheesh.

I tried playing w/ the seating depth and CCI BR2 primers (like I said, they've always worked well for me, so I 'trust' them). Apparently the gun still likes the Scenar 15 thou off the lands, but thats only because that group is slightly less horrendous than the other seating depths (2.5 MOA @ 300yds).

Not sure whether to go back and re-run a modified test (mid-to-higher end of the scale, CCI BR2 primers, 2.326" seating depth) w/ Hunter, or wash my hands and move on to the slower stuff. Biggest reason I wanted to use this stuff is that it is supposed to be pretty temp stable (I realize that H4350, H4831SC, and H1000 are all Hodgdon 'Extreme' powders and as such are supposed to be pretty stable as well) and meters like sugar... almost no point to weighing charges w/ the Ramshot powders. That said, I'd found a way around that w/ the Hodgdon powders... that dang Lee Perfect Powder measure. PITA to set, but once it's set... its about as good as it gets for extruded powders.

Monte