Here's a 270 gr TSX taken out of a Lioness I shot this year. Muzzle velocity was 2750fps. Shot distance was 30 yards. Would you trust this bullet on a Cape Buffalo, at that velocity? I also took an Eland with the same bullet at 250 yards and the bullet penetrated the whole chest cavity and exited. So, I think the somewhat high velocity of 2750fps would be too much for close range buffalo hunting. Once they slow down a bit, they seem to work fine. But, if you're going to shoot 2500fps or less, why not just use a 300 gr.?