I've never got one back rusty, but as Swampman stated, the grease or whatever they put on them is nasty stuff, and the bluing process will stain patches brown for quite a while until it's been cleaned many times, do a little research on bluing, it's just controlled rusting, you'll find it in the bores as well since they don't plug the bore before they blue them, so the bore gets blued too, you'll get brown patches which appears to be rust, but it's not like a truly rusted bore. I have a sectioned barrel that Larry sent me that clearly shows the bluing in the bore.
Tim
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