Longest shot I made on a white tail in PA, was just over 500 yards. It was with a 25-06. For any long distance shots that is the gun I chose. I have a 25-06 for the sole purpose of long distance shots, killed several deer with it. It is not my normal deer rifle of choice, that is a 308, however, terrain is the decieding factor on which rifle I carry. I am not a magnum guy, so I dont own any mag's, cant help you with those. I do believe the 25-06 is the caliber to go with (not including the magnum rounds) if long distance is your prime goal. However, no caliber can overcome the lack of practice, that means whatever you plan to hunt with, you need many hours of practice. During the summer months, Ground hog hunting is great practice for your deer rifle of choice. Good luck in whatever you choose.