That's some nice shooting there. And a good powerful load. Now all you need to do is get within 70 yards of an elk. Keep practicing. I think you might be on to something there. I shoot a .54 caliber Mountain Stalker which is the Bass Pro version of the Bobcat. My rifle does real well with 80 grains of Triple Se7en a wonderwad and a patched roundball. I have actually shot powerbelts out of the rifle and it did surprisingly well with them also.

Good luck on your elk hunt.