I killed my elk this year with a lead round ball out of my primitive Hawken. The ball has a BC about like a rock. It makes me chuckle a bit on what some guys think isn't enough bullet for elk, or even deer.
I've grown tired of the heat in muzzleloding season. Next year i'll use my Swedish Mauser 6.5x55mm during the 3rd rifle season. That old gun has got me plenty of elk and muleys with a 140-160gr SP.