I took elk with a 54 cal Hawken that use a 230gr round ball and 130gr FF black powder around 40 yrs ago I dought they are much tougher now.
The important things are know your gun and pick the right spot to shoot at and hit it.I hit both of mine in the ribs at the back edge of the shoulder and about half way between the bottem of the chest and the top of the shoulder.
Try them all with 100gr up use the one you can hit a coffee cup at 100yd with all the time. Lee