I am looking at building a new switch barrel rifle. The components i am looking at is a bighorn reciever in a short action. And using the wto lug for the switch barrel. The calibers are 6 creed for prs in a chassis stock. A 6.5 rsaum and a 30 caliber of some sort in a bdl type stock for hunting. I am looking at running the hunting rounds long. What suggestions do ya'll have for the 30 caliber, mainly for elk and nilgai under 400 yards, and what internal box to use for the bdl stock? I am not reloading yet. But , I am getting components together to do so. Any help would be greatly appreciated.