I'm pretty frustrated with this. Being my first 300WBY, I didnt realize how restricted I'd be by the longer case in a standard action length. I've shot some 1/2 MOA groups, so I know its capable, but that wasnt with any bullets I want to shoot. Single feeding isnt even a deal breaker, but having to remove the bolt to eject a live round is... that just doesn't give me much room for these long high BC bullets.
So I have a 1959 German, a mid 80's Japanese, 2008~ and 2015 US plus a WIN M70. I shoot 180 Nosler BT in my German, 24 inch barrel, 12 twist, less than half inch, better shooter can do much better. I shoot 200 grn in my Nosler AB and PT in the Japanese and Older US, again less than 1/2". I shoot 180 TSX in the newest one, 0.43" at 200 yards. Haven't played with the M70 yet. Most people I know shoot 200 grns.