I know cold bluing is not as good as hot blue, but I have no access to hot blue, so I did a cold blue on an old Remington 511 rimfire for a brother in law. The rifle was a total bucket of rust before, and looks about 1000% better, but I'd still like to make it better, if possible.
I did a cold blue on the receiver/barrel, it was completely sanded starting with 150grit to 2000 before bluing, in some places, actually filed, it was that deep.
There are some slight water like marks on it though, is there an easy way to get rid of those without ruining the blue?
I repeated the process about 6 times in the one night, and let it sit overnight, after oiling it down (as per instructions on the bottle).