Haven’t tried it yet, but one of my odd notions is that a roundball may shoot okay in a fast-twist barrel placed in the appropriate sabot. I have some .457 RBs and .50 cal sabots for .458 bullets.
I always suspected that a big part of the problem with RBs in barrels twisted for bullets was the depth of the rifling more than the twist. I’ve read that original Hawkens were twisted 1-48”, but obviously they did ok with RBs and lots of powder.
