Thanks everybody for the posts. I'm gonna try the 4895 first, cuz I have some. I'll start with 36 G, and prime it with some BR-2s behind those 120 hornadys. I'll let everybody know how it shoots.
BTW, this is a Bergara Encore barrel in 24". It has a very nice chamber, tight and straight. The rifling is shiny with few tool marks, and lockup is good. It shot OK (9s with reduced H380 45G and 140 Noslers), but I know that it'll do better.
I bumped the shoulder to about .002 HS clearance, and the 120s about .005 off the lands. We'll see what happens tomorrow with 36.5 of H4895. This is one of Hodgdons Extreme Powders, its supposed to be pretty temperature stable. Hopefully if it proves to be in the ballpark, I can tweak it a little more and load up about 20 to last a few years.