I never use water on my Black Powder guns to clean them . Metal and water dont mix .
The first time I got a cheap Pietta Navy I cleaned it with hot soapy water , as it dried in a matter of seconds , every nook and cranny rusted before my eyes . NOT GOOD !
After that I use commercial BP cleaner and lots of patches and a toothbrush to remove any residue . Then I oil everything up and spray the entire gun down with spray Sillycone . I have never had a rusted gun in over 25 years now doing this . Water is Ole Skool , and some Ole Skool things have gone to the wayside for a good reason .
We dont season our BP guns anymore either , because the materials used now are not Iron and they wont season anywayz . Water is the same thing , there are much better ways to clean a BP gun now . Just my not so humble opinion is all this is , but it works .

Oil and water dont mix , and neither does water and steel .