As a very young deputy sheriff, I was taught to take the grips off my blued revolver, put the unloaded revolver in the oven on it's lowest setting, wait until it was fairly warm, then put on the turtle wax. I was told that the heat opened the pores in the steel and the wax filled the pores, and when the gun cooled, it would protect against rust. For those who doubt the effectiveness of this method, my Dan Wesson that I carried in a regular border patrol holster and then later the "judge" holster, showed no rust, even after being caught directing traffic in a rainstorm that drowned my Motorola belt radio.
The Officer that taught me this has passed on, and to honor him and thank him, I just wanted to pass this on.