Kuhle--
I have a slow twist rifle, a 66 inch, so I either have to use RB or short conicals, it is a .50 cal. I have not shot a deer with it, but I like to shoot a Hornady 240 grain "PA". These seem to be about the same as the Buffalo "Ball-ets" that I can't seem to find. I get the Hornady's from Midwayusa. I have shot these into something solid and they flatten out considerably, I use 80 grains of Pyrodex RS behind them. I think they are going appx. 1500-1600 fps and would do a number on a deer within 75 yards or so. I don't like to mess with RB and patches yet, maybe I will learn to like them sometime.