First of all...forget about all that 25 yard stuff. Set the scope at 100 yards, assuming your hunting whitetails in mixed cover, to 2 inches high. Next, don't guess where the bullet is going, go to a range and shoot the thing as far as you think you'll be hunting. Don't rely on Ballistics Tables, their fun to look at but not reliable for real hunting. I think you'll find those 300-400 yard shots much tougher than they seem. With that setting, your load should be in the 4-6 in low category at 300 yards, that's a long way out there when shooting at game. It's easy off the bench but MUCH practice is advised. Shoot often and shoot a lot!!!