I have several weapons that are stored in my home , yesterday I looked in my case for my fAL and there was a very light coat of rust, very light building up. I have seen it before on my SAR and on my bolt action. So yesterday and from now own, I will wipe them all down with a light coat of hoppes lubricating oil but they are all stored in daskil plastic cases. What could I be doing wrong, or will the light oil wipe down cure it? Im in WA state will humidity matter at this time of year?