another book from Safari Press, the Perfect Shot II, covers this subject extensively, same author I believe, bit pricey but we'll worth the coin, copyright 2013 so has all the updated bullets and may help make your decision if you are hunting other animals besides buff. If buff is the only thing on the menu, go to page 80 in the book and check out the pic of the 380gr rhino along side a 600 gr bullet pulled out of the same buff, that will make you think
Great read at any rate