The 300 WSM would be a good choice as would several others mentioned. And you must practice at these distances. I believe having enough velocity at impact to expand the bullet is important, and bullet construction really comes into play beyond 600 yards. And you must practice. 1/2 moa accuracy is virtually a must for such shots also, so custom guns and fine tuned handloads can go a long way in this regard. And you must practice. Good quality optics with reliable, repeatable turrets are needed.

Did I mention practicing at these distances?


Dying ain't much of a living boy...Josey Wales

Molon Labe