Brokennock
Cannon
+1 on the GunzillaWell soap makes water wetter and is the reason it will de-solve more and faster than water alone. Warm water heats metal and causes it to expand which in turn enlarges the pores in the steel. So warm soapy water does translate to a deeper cleaning power than water alone.
Barrel steel warms up from the combustion of burning powder which again expands metal (opens pores) and the pressure drives the fouling into them.
Warm soapy water gets in and desolves fouling better than clear water alone. Clear warm water cleans better than clean cold water and when soap is added it results in a force multiplier.
I believe when the pores in the barrel steel are opened by warm water than a good water displacing oil such as WD-40 or Kroil should be used to get the rinse moisture out of the steel pores and then wiped dry with a clean patching. The final step is a good preservative left in the bore. I believe a good natural oil not petroleum base product is the best way to go about this. Bear grease was touted by Ned Roberts of percussion era fame to be one of the best along with Sperm oil which is not available now days.
I have found a product made of plant oils which is both and excellent cleaner and very good bore preservative know as Gunzilla. It is the best lead and carbon remover I have ever incountered to date when applied by a tight cloth patch on a jag.
I have a product that removes carbon better, but isn't plant based and I don't use it with muzzleloaders.
I've found Gunzilla to be an excellent lock oil in that it is very thin so doesn't take a lot to do a thorough job, and, it doesn't seem to freeze.