EXPERIENCE?????  You didn't say you wanted THAT???  Well, I replied to the wrong thread?

Battle hardened late WWII I would think should be getting a little rust, so you may be just about right.  It had been in a good bit of rain, mud, snow and sweat by that time.  I personally probably wouldn't go too heavy, unless it was found in the woods years after the war.  Your rust looks an awful lot like worn paint and that would certainly be there!

Rob.