RE: WD-40
WD-40 is a fairly good cleaning agent. However, IT WILL FREEZE! A fellow I rabbit hunt with sprayed his .410 Rem 1100 with WD-40. About 2 years ago, we were hunting in January and the temp was right around zero. The action froze up tighter than a drum. He had sprayed it liberally with WD-40, so moisture was probably not present.
I've not had any problem with it when I've used it, though.
I now use a product called Nelco Free-it. It's like WD-40.
RIG is another quality product.