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How are the steel particles going to rust if covered with a properly applied water proof finish ? I have stocks refinished over 50 years ago---no freckles. Sounds like a myth created by some gun writer looking for something to write about. Or maybe he stores his gun in the bath tub.
Is this myth similar to the ones about weighing primer and heavy crimps being needed for best accuracy?
First, very few stock finishes are truly waterproof. All oil-based finishes readily transport water through them. Ordinary 100% oil finishes will pick up and release atmospheric water faster than dry wood. Water stains on oil-finished furniture is an example of oil finishes soaking up frank water which they do slower than vapor.
Epoxy, cyanoacrylate, and some paints are waterproof.
It is not even close to a myth and has been well documented for well over 50 years.
To find the steel particles or the rust freckles may take a bit of magnification. The haze they produce can be seen without magnification. You have undoubtedly seen it without recognizing it if you have looked at many guns treated with steel wool.
I always suggest a test board be made just to prove how wrong I am. You will be doing yourself a favor because you will no longer be "that" clueless guy arguing against something that is so completely true and obvious.
No ill will intended nor taken.
