Poacher

This the first year that I will use my Rock River Predator. I have killed deer into the next zip code with my 25/06 but I have handed it down to my son what I am trying to find is a bullet that I can load that will have expansion at long ranges (600) as well as 50 yards. I don't want to hear about shot placement I am not a rookie shooter, but I don't have experience with the 308 any ideas