if it is just Whitetail, .243, .257 Roberts, 25/06, 7mm08, .308, .270, .280, 30/06, 30-30win, 35rem, 45-70, 444 Marlin, kinda depends on where and style of hunting. I prefer .243, 7mm08 and .308 but thats just me. Whitetail are not made of ballistic steel that some lead to believe. Take out the pump station, air compressor or central nervous system and you have meat on table. Shot placement is far more than caliber as long as you choose caliber wisely. If heading to large foodplots, beanfields or wide open country some of the flatter magnum rounds might help a touch with trajectory.