Ideas? Thought I might start with Re 15. Varget and IMR 4350 might get a try but I only have 50 of them. I would like a few to shoot game with. Thanks "D"

I've been working up loads for a 270 gr FN in my 375H&H No 1. Reloader 15, 60, 63 and 65 gn.
The 65 was to hot, 63 zeroed at the same spot as my 300 gn Sierra load! at a 100 yards. The 60 was a good light lead load, it was about 3" lower than my 300 gr Sierra load at 100. I'm going to work with that for now. I'll have some speeds in a few weeks when I get my Chrony back, it had a run in with a 45 ACP. Not mine.

RL-15 From 62.7 grains to 76.0 grains
Remington 9-1/2M Primer

Varget From 61.1 grains to 75.1 grains
Remington 9-1/2M Primer

IMR-4350 From 72.0 grains to 81.5 grains
Remington 9-1/2M Primer

And you should try...
H-380 From 69.0 grains to 81.5 grains
Remington 9-1/2M Primer

Don't waste them. Start with 73 gr Rel 15 or 77 gr IMR 4350 and work up to at least 2800 fps, more if your rifle has more than 24" of barrel. Use magnum primers. Load one at each load to determine speed if your chronograph will read every shot. Load them touching the lands if the mag box will allow that, otherwise as far out as possible. When you hit the speed you want, load 15 at that load and overall length. Shoot three for group, put a dry brush down the bore and let cool. Push the next three .04" deeper into the case and fire for group. Repeat till you determine the sweet spot for your rifle. You are done inside 20 shots - speed and col.