I've been watching H1000 in the 7mmMashburn Super for a year now....it does not give the very highest velocities but is only 50-75 fps off Retumbo, but spreads are very low,and POI consistent winter to summer, out to 600 yards.

I have not touched the scope settings since the rifle was zeroed about a year ago.

I agree with John B on the temp thing,at least from what I can tell.....and noticed years ago that a powder that looks lousy in one cartridge, does well in another.....for example, I found IMR 4831 to be "good" in the 270 over various temps, but not so in the 7RM,where it lost velocity in the cold.

Sometimes, I think powders that give slightly compressed loads do better,but not sure why.



The 280 Remington is overbore.

The 7 Rem Mag is over bore.