FWIW, when I hunt with a muzzleloader, it's normally a .54 cal flintlock Lyman Great Plains Rifle, BUT...
I have an oddity of an inline I picked up used here a decade or more back - a Pedersoli Gamma 9000 .54 cal. What makes this an odd rifle is the twist; it's not on the rifle anywhere and I can't find it online, but a cleaning rod and a Sharpie marker make it out to be about 1:60... an inline with a round ball twist, go figure. I've never seen another one, and there is very, very little info online about it - most of your hits if you search are going to be my own posts seeking information about it.
