I will be Hunting deer will be 20 yards - 300 yards. The 300 win mag is to much HP and ton of meat damage. What caliber do you use with, that don`t destroy a lot of meat.
Meat damage is not so much about caliber as it is about bullet selection and shot placement.
If I were you, I would probably be looking at something like the .257 Roberts, and a Barnes TSX bullet, for behind the shoulder, lung shots.