Originally Posted by
Mauser308
Why? They used carbon HSS steel tooling to machine it...
Most small parts aren't stainless as SS don't tend to have the strength of steel fasteners. Springs etc are also carbon steel.
If you use oil on the rust, the oil acts as a lubricant and floats the rust particles so that they don't scratch the steel underneath which won't show on the metal finish. If stainless is rusting, it's already contaminated and you need to get the rust off, and the easiest way is to use oil and steel wool and then subsequently clean the oil/rust slurry off and re-oil.
There really isn't any other way that is as easy and as successful as using the steel wool/oil to clean rust spots that I know of. Possibly careful scraping with brass scrapers, but you still need to remove the remaining spots.