I may have some input of value. I contacted l an oil specialist directly and asked about metal protection on machined surfaces ( steel ) required at my job for long term storage ( multi decades ). To make a story short, we bought a 5 gallon bucket of Kotespec Total oil. I tried it on storage of firearms from leftovers, found it was adequate. Just like any protective coating, it should be cleaned before firing. It is very liquid when applied, smells good, well (if you're into metallurgy), it dries off and leaves a small film on the surface. I'm not sure it is available for the peasant though, as 5 gallon was minimum purchase and I bought it in the name of the company I work for. I find it more adequate than any commercially available product on the corner store.