Well since factory is what your going with and Western states my top three would be:
1. 6.5 PRC
2. 7mm Rem Mag (Not 7PRC!!!)
3. 300 PRC
1. 6.5 PRC
2. 7mm Rem Mag (Not 7PRC!!!)
3. 300 PRC
I've taken over 500 whitetails, a 176 & 184" mule deer, Coues, Carmen Mtn. whitetail, and 120" blacktail with my 6.5/.284 XP-100 handgun, plus a whole lot of African game.
This round kills way beyond what you would expect with much less recoil than the bigger rounds.