If I take some of my nicer blued guns hunting in the rain they WILL get rust on them.before I get back home .Like they used to hear them say about a ford "At night you can hear them rust".JMHO it's just a fact of life with quality blueing.But the good thing is it is not a problem.Just let the gun dry out then clean like you normally would.No harm no foul.Long term just coat them with a good oil and look in on them about once a month just to be sure.Or you could always fill them up with cosmoline....................J/K