IF you can find it, and theres reports of some temp stable issues but I have no first hand knowledge of that that's why when I can get H1000 to work it's a proven temp stable powder which I will take over some FPS.RL26 is the magic powder for this case.
I get great accuracy and velocity with R26 and 180 Berger's in my 7RM but pressures get very screwy when temps are over 85 or so. Retumbo is about 120 FPS slower but consistent pressure and shoots knots in my rifle
I would. I used reloder 26 with hbn coated 180's and was able to hit 3050 fps as a max, which happened to be right where a good node was, that was around 70 grains. The next node down was in the 2950 range, still excellent performance, with around 67 grains.
I did a load work up with naked 180's and H1000, Saw max pressure around 2970 fps, with 70 grains. Load workup was like this:
180 VLD
Federal brass
CCI 250
Seated .010" off
H-1000
67 grains - 2838 fps
68 grains - 2880 fps
69 grains - 2953 fps
70 grains - 2969 fps
This was in a SAAMI Remington chamber. Hope this helps.