I have also gone as long as nine days without cleaning one with no signs of rust or corrosion.[/QUOTE]
I can't agree with that as I would never leave my BP weapons even overnight with cleaning. Once I did leave my 58 cal overnight and normal cleaning next day wouldn't remove the "stain" from the chamber. I did use x fine valve compound on a swab to remove this stain after repeated strokes with the swab. No I'd never leave any of my weapons without cleaning immediately after a day of shooting. It's up to each of us as to how we want to keep/preserve our expensive weapons. I paid too much for mine to take a chance with possible damage, however slight, it may be, as this slight, hard to see damage will collect over time and might become more than we can correct with delayed cleaning.
Just my 2cents worth