I haven't used the Sierra bullet, but I have used the 175 grain Speer Grand Slam for moose when I was in Alaska!
My rifle is a Remington M-700 BDL, 7mm-Rem Mag!
The load that I used was 56.5 grains of IMR 4350!
I had pretty good accuracy, if I remember correctly, I could put 5 in a 2 inch circle at 100 yards!