Thinking about trying these to see how flat of a line I can get out to 500 yrds. What powders are giving you the best accuracy/velocity combination, and what kind of velocities are you achieving.

Looking mostly at the Barnes TTSX and the Nosler E-Tip...that B.C. of .469 for a 150 grain pill is appealing.

Winnie I've tried this with 2 or 3 different 300 mags and found the same thing with all of them. On paper this seems like a good idea. Accuracy with all the 150 gr bullets was so-so at best. When you did hit something with the 150 gr at hyper velocity meat damage was terrible. In all cases the 165 or the 180 gr bullets produced far more consistent groups.

I've had great success using Re25 in my 300 WM. It also worked in my gun with 150 gr Sierra and NBT bullets producing ~3450 fps with a 26" barrel. If for your gun, Re25 won't bring-up the pressure, I'd suggest Re22 or MRP.

But, I've settled on 180 gr Accubonds and NBTs producing ~3300 fps with Re25 (IMO absolute MAX).

Lately, I've had success with the 190 gr LR Accubond, also using Re25. This is now my 1000 yd plus load.