Years ago, I got into nicer air rifles, and I started using a protecting oil made by Beeman, that was highly recommended on the forums. While the airgun phase eventually passed, I still have and use that oil, particularly on the bores and exteriors of blued guns, put away in their cases. I've left guns stored this way for way longer than I should've ( like 1-2 years!) but I've never once had a bad surprise when I inspecting a gun with this oil on it. The stuff is super-thin, and always feel like a insufficient coating, but somehow it works great. It appears to be discontinued ( like so many other products that didn't cost a fortune, and actually worked.)
It's this stuff here......

It's this stuff here......
