Cold water by itself works fine, hot water better, but watch out for flash rust. which comes back as rusty color on your wet patch. I just use cold water when I run out of my MAP solution. I don't remember whether it's warm water, or boiling water that causes flash rust...might be boiling. I've always used MAP for the last 20-years and just cold water when I run out of that. 3 in 1 oil is a light machine oil which works fine. Not sure what the difference is between that and gun oil but since it takes so little to use for protecting the lock and the barrel, I use Hoppe's gun oil.Thanks Gentlemen! Gonna be honest with ya, I've been using commercial black powder bore cleaner and thinking maybe some of this other homemade stuff is better. Looks like hot water and dawn liquid is what I should of been using and will start using with 3 in 1 oil to finish after drying