The OP asked about protecting the outside of his weapon. Not lube. I've used WD-40 to wipe down my guns since 1975. I used to bird hunt a lot, shoot skeet occasionally (skeet range is where first saw "everyone" using WD-40). I wipe down my weapons everytime I handle them. And, none has any rust or "gummy" substance on them. I use WD-40 to clean and protect and remove water, if needed. NOT lube.

