Re: What caliber? 6mm rem or 25-06
I'd go with the 25-06 and use either 100g or 115g NBT's.
I've only killed 2 antelope, 1 with a 300 Win mag 180g NBT at about 250 yards, DRT, and the 2nd with a 25-06 and 117g SGK at 550 yards, also DRT.
25-06 has enough power to kill antelope waaaaaaaay out there.
I've had 4 25-06's over the years and not 1 of them was ever finicky with loads. Matter of fact, they have been some of the better shooting calibers/rifles I"ve owned by far and weren't picky what so ever when it came to bullets or powders.
Theres nothing wrong with the 6mm though...