I went to the range the other day and fired my first 300 rounds from my XD-9. everything FUNCTIONED flawlessly and the accuracy was great from a subcompact. One thing that boggles/cocnerns me though is the bright silver colored metallic accumulation on the muzzle crown. It seems to come off with a strong fingernail pick, but it's going to be some work to remove it altogether. I used wally world WWB and put a couple of rounds of Speer Gold Dot +p+ 9mm Luger through it but that's it. Accuracy seemed to get better as I shot, which I attribute to my learning the weapon more than anything else. Theoretically I would think that a build up of crud on the crown would start to hurt accuracy. Any ideas what this is anyone? :?