I took the A2 off of my upper and noticed that the muzzle had a good amount of carbon build up. I cleaned it up with some clp using wood and plastic toothpicks to scrape away the carbon. Once I got it all cleaned up I noticed what looked like a scratch or pit not far from the crown. I was worried that it might be touching the crown but my eyes weren't good enough to tell so I busted out a macro lens and took some pictures. The pictures show things pretty clearly. I was happy to find that the crown looks really clean and that pitting was distinctly separate from the crown. It looks to me like perhaps this is just what happens as part of the hard chrome process? Here are some pictures: I am thinking that everything is probably just fine? Accuracy has been acceptable so far, maybe even really good. I have been blasting steel plates out to 200 yards and having a lot of fun, no precision shooting yet. [span style='font-weight: bold;']So is this anything I should be concerned about?[/span] Here it is with the new flash hider on.