Put down some cash today for a lightly used H&K USP 45 V1 and noticed the extractor was turning a red purplish color. I was just wondering why HK's do that? Because I have seen many in the past which have had the same problem including some HK's being sold on here. It's not a big deal to me I was just curious. Also does anyone know of a good source for picking up some spare mags?