We would like to offer advice to our customers that we have learned through our years of experience.
Black powder firearms need only hot water to clean them. You can add some dish detergent if you like. Most important is to dry them well after cleaning followed by oil. You should run a patch back through them in several days after cleaning to make sure no rust has started. Some of the bore butters on the market seem to work, and in this case you would use them in place of oil.
Always protect you muzzle from unneeded wear. When using you cleaning rod always protect you muzzle with some form of muzzle guard. We have seen muzzles worn to one side from repeated cleaning with the gun held in the same position and being rubbed with a dirt embedded cleaning rod.
By far, one of the most common problems for rifles not to shoot to their full potential is to have the barrels too tight in the stock and not having the underlugs (tennons) slotted. Whether you build the firearm yourself or have someone build it for you, please check these two factors. Barrels should be allowed to move somewhat in the stock. Tennons should be opened up to form a slot to allow the stock to move back and forth during the changing seasons and also with the heating up of the barrel during firing.
We do not recommend coning muzzles. Some do with success, others not with success. This is one area where we will not provide warranty if a barrel has been coned.