Bore butter is a bullet lubricant for conicals, that some guys use as a protective coating when the gun is being stored. I used to use it for storage, but now I just use regular gun oil. Soapy water is popular for cleaning black powder as it easily removes the crud, but most people shooting inlines just use solvent-dampened patches. I make my own with patches soaked in BP solvent, and then I squeeze out most of the solvent so they're just moist. Don't forget the breech plug and the threads inside the barrel.