In Colorado, for muzzleloading, .40 caliber and larger is required for hunting deer, Pronghorn, and black bear, .50 and larger for elk. Roundball was fine. However, several years ago, Colorado Parks and Wildlife decided for deer, Pronghorn, and bear the minimum projectile weight needed to be 170 grs. This means using a conical for my .44 percussion sidelock. It only shoots a 120 gr. .430" roundball and has a 1/60 or so twist. The groove diameter is .448", and the land diameter is .442". The barrel was made by Miroku in Japan, and has very narrow, beside shallow, lands. I'm thinking a light .45 bullet sized down to the appropriate diameter might work. It would probably stabilize where a heavier mini ball or similar might not with the slow twist barrel. I already cast Lee 200 gr. SWC tumble lube bullets which come out of the mold at .451". It would be easy enough to to make a quick and dirty sizing die on my lathe. I'll use a blackpowder lube and probably a card or fiber wad between the bullet and powder for starters. Has anybody else had this problem or any thoughts on a solution? I appreciate all input.
For what it's worth, I've killed Mulies with both .44 and .54 roundballs. The .44 killed them just as dead and quickly as the .54. My experience makes me think a 170 gr. requirement is a solution for a non existing problem.