An old round ball target shooter who sold me his chunk gun several years ago also shared a great idea about how to get consistent accuracy from the gun. He used 100% cotton denim for patches, lubed with machinist's water soluble cutting oil. It takes a little time and effort, but getting cloverleaf groups with iron sights at 60 yards from 50 caliber round balls is worth it. Chunk guns, and muzzleloaders in general can be very picky about the thickness of the patches used with round balls. Mine likes 100% cotton denim that measures .017" when tightly compressed with a pair of dial calipers. If I use .015" material, the groups open up noticeably. I'm shooting .490" pure lead balls, weight-matched to +/- 1/2 grain over 78.0 grains of 3-F Goex powder. Half a yard of denim from the local fabric store makes hundreds of patches.
Wash and dry the material and cut it into strips about 1 1/4" wide, then mix up a pint of water, a few drops of dishwashing liquid, and about 1/4 cup of water soluble machinists' cutting oil. Put several strips of the denim and the water/oil mixture into a quart mason jar with a tight fitting lid, and shake vigorously for a minute or so. Fish the soaked material out and lay it out in the sun on a cookie sheet or other piece of non-porous metal and let the water evaporate away. The oil will stay trapped in the fabric and have a slightly slippery feel when rubbed between the fingers once the water dries out. I leave the fabric in strips about a foot long, seat the ball flush with the muzzle when shooting, and trim the excess off with a straight razor, a super-sharp patch knife, or a box cutter blade.
If you're hunting with this type of patch, be sure to add a felt cushion wad between the powder and the patch. They tend to smolder if the patch gets exposed to the powder burn and we don't want any woods fires, now do we?
Jerry
