Pastorp, I hunted in SC Alaska for 27 years, most of that time with un-oiled Contenders. No rust on the internal parts, I always wiped down the outside with oil though, as the instructions suggest. I hunted Kodiak every Fall from tidewater up to 3500 feet, but wasn't drenched in salt water.
The problem with the oil is it attracts dust and grit, concentrating it at the critical points, which is where the oil seems to congregate. This causes sticking and malfunctions of the fly/intercock mechanism. I always hunted with a chest holster so the T/C was kinda protected...it got plenty of sweat but no rust. Perhaps I am more careful with my firearms than others are.... :?: