I use Hawk bullets 180-250 G. in my 71's, hunt Alaska with it. Killed a few moose, bears. Never shot BB. I use mostly Northern Precision in my 71's in .450 Alaskan, 400G. does the job........ forget the load ,but Not at max, don't need to be super hot. One can't shoot that real hot stuff fast any way. And a sticky chamber at the wrong time... oh boy.
Cisco