If one is only getting 2800 from a 270 with H4831 and a 150, one needs to either add more powder, or replace the barrel on the rifle. Perhaps both.
As Seafire said, you can not get enough H4831 in the case to hurt anything with a 150. Fill it up to the top and listen to the kernels crunch as you seat the bullet. Been there, done that with the '06 and 190s.
Seriously, Hogdgon #26 says 150 gr bullet, 58 gr H 4831 at 3015 fps and 52600 CUP.
Nosler #8 says 55 gr H4831 for 2900 fps.
With my experience, if using only standard cup and core bullets, I would be looking for 2950 fps with 150s and H 4831. I would bet the primer pockets would be good for ten reloads.
If loading mono-metals or partitions, I would call 2850 fps good enough.
