Bonded-core soft on the point of the shoulder. No need for solids on buff these days IMO, as other posters have already pointed out.

A Woodleigh, for example, will break the first shoulder, pass through heart/lungs/whatever, and almost always break the second shoulder. Depending on calibre, it may pull up in the off-side shoulder after breaking it, or pull up under the hide. They rarely penetrate completely after breaking both shoulders in my experience, which is on Asian buff rather than Cape buff. The former are probably heavier in the shoulder than the latter anyway.

The only exception really is if the bullet breaks the shoulder then centres the spine where it dips down between the shoulder-blades, in which case it may pull up in the spine. Very dead buffalo, in any case!