I look at this differently. I am more concerned about the rifle than the cartridge. I have killed a number of eland with a 270 Win using 130 Barnes monolithic bullets, TSX TTSX, without incident. That combo will penetrate 34-36 inches of bone and meat.
That said there should be an opportunity for the buffalo found there so something bigger is warranted. I would want a rifle with a 20-22" barrel and no more than 8 pounds. I would pick the 9.3-62 and use a Barnes mono.
Rick, didn't you take a few eland with the Bitterroot 130 from a 270 Win as well? I thought Bob had sent me a few of those pictures. Can't remember the animal taken though.
