Buy several thickness patches and see what your rifle likes. It's just one of those things you have to do. Sometimes it's not just ball and barrel diameter that determines your patch thickness. Every manufacturer make different depth riflings which makes a big difference. I've seen anywhere from .002 in. to .022 in. deep riflings. For muzzleloaders I like deep riflings. My Green mountain barrels range form .016 in. to .020 in. I had them made that way because I often shoot at rendezvous a lot and don't like running more than one patch between shots. I also hunt with my ML's almost exclusively over my center fire rifles and want to make sure I can get a second shot off fast and deeper rifles are easier/faster to load.
Good luck and be safe. Boomer
Green mountain barrel .58 cal Lefty
Green mountain barrel .62 cal
Green mountain barrel .36 cal
Traditions Hawken kit. .50 cal
CVA Flint lock .50 cal
CVA cap lock pistols in .32, .36, .50, .58 and .62 cal.
CVA Wells Fargo revolver .32 cal
CVA Squirrel rifle. Lefty .32 cal
CVA Squirrel rifle. Righty .32 cal
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