For plainsgame I would be satisfied with any good 300..I use a 300 H&H handloaded with 200 gr. Noslers and it will sure kill an Eland...I have never found Eland hard to kill if you stick a properly constructed bullet in the right spot.

A 30-06 or .270 will also work fine for plainsgame as will a 338....

My idea of a perfect combination is a 270,7x57 or 30-06 (take your pick) combined with a 338 Win shooting 210 gr. Noslers.....I like the idea taking two guns on a plainsgame or any kind of hunt if transportation of the extra gun is not a problem.....