Recently sent in to Kahr my 380 to be reworked. When they sent it back it was dirty from them testing it buy not bad. Noticeable but not bad. Since then I shot approx. 150 rounds thru it. White box Winchester, American Eagale and Ram. Cleaned today getting ready for a trip and BOY was it black, really black. It cleaned up good and easy but black. Thought that was interesting. I clean all of my others and they weren't near as bad. Just observing.