There are a number of solvents on the market that provide an alternative to putting water into your barrel. Unfortunately, NONE of them provide a better method of getting black powder or black powder substitute fouling out of a barrel.

I have found that the best and fastest way of cleaning a barrel that has some sort of a cleanout screw at the breech ( even if it is just removing the nipple) is to pour two quarts of boiling water through the barrel from the muzzle using a funnel and wrapping a towel around the barrel to provide a handle to allow you to hold it steady while pouring and preventing you from burning your hand.

As soon as the water has drained out, the barrel will be hotter than a two-dollar pistol, and you next swab it out with three or four clean, dry patches. When done swabbing, your bore will be both totally clean and very dry, in addition to being hot!

Let the barrel cool. Then swab the bore really well with a patch saturated with Birchwood-Casey Sheath (Barrier, I believe they call it now??).

Your bore is now clean and fully protected from rust & corrosion, AND, since the Sheath fills the pores of the metal and then dries completely, the next time you go to the range, you can load up and fire without having to swab out oil/grease before loading!

Water is the BEST solvent for black powder fouling, and for the salts from corrosive primers in old military smokeless powderammunition.