I always thought the old Krag had a neck that was just about ideal in length for a wide variety of .30 cal. cast bullets.
I am not much for "wildcat" calibers. I have done sufficient damage to my hobby budget with the commercial numbers already in hand, thank you very much. But one caliber could jolt that adherence loose, I believe--the 8mm-'06. With the 9.3 x 62 on hand pushing 250 grainers close to 2700 FPS, there isn't much "need" for the 8mm-'06--but when did "Need" become a pre-requisite?