My guess is someone soaked it in WD 40 and put it away. In time WD 40 turns into something like Loctite.
No it doesn't. My dad didn't use anything but WD-40 on his guns for many years. I don't think he fired a shot in his last 20. After He died I got his guns. They weren't gummed up or gummy. They functioned fine but were a little on the dry side.