Re: What caliber? 6mm rem or 25-06
115grn with RL22 or IMR4831 will do quite nicely in a 25-06. If you want the added weight, I downed quite a few Whitetails with the 120 Sierra Game King. Works like a charm. At that distance for that rifle, BC will play very little unless you have some pretty stout winds. This should offer better barrel life.
To confuse you even more, the 6mm in a 115 is the heaviest, and give you awsome ballistics. What twist is on the 6mm? Even if you could shoot the 105 A-max or the 107 Sierra, you will have a great caliber for antelope at longe range.
Just my humble opinion,
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