If you are in Mississippi (I don't think rhinos have migrated there) then I reckon any factory cartridge 300 grain bullets or more will leave a blood trail that Helen Keller could follow. The factory rounds are a bit nerfed but then, what can gracefully survive a 45 caliber round digging in to it at rifle velocities? If you are concerned about needing more pounce, I would check out Buffalo Bore and Garrett cartridges. I have a Ruger #1 in 45 70 these days and it is a delight to shoot.