What are you going to be hunting with it? I'd recommend you use the same exact load you're going to be hunting with. I can't answer that question with certainty as all rifles shoot different, even among the same make/model/cartridge. I do know that the 5 different 300 win mags I've owned all "liked" 180 gr loads regardless of brand/model, and most really shot anything 168 gr and above excellent.