I will say for a wad under the conical a wonder wad is excellent:I would use a 54 cal wad in a 50 cal. barrel much tighter seal: I would not pass or try a round ball in the new englander as long as your barrel doesn't have the QLA a RB with 90 grains of 3F goex will stop most any deer if the shot is placed right.
I would also look into REALS CONICALS 320 grainers here another good lead bullet:I wonder if black jack hill over at e bay is still casting:He does cast an excellent bullet