Funny this issue showed up her and at the other forum. This weekend I got to shake out the new DPMS carbine, and side by side it with the Sport. I noticed the Sport spring clunking in the tube under my ear for the first time. I shook the rifle 2 times, all seemed fine, and we went back to shooting. It takes a cleaning and a couple rounds before the spring starts to sing to you. FWIW, my Sport hit 3k rounds this weekend!!! Accuracy is still good. No signs of any unnatural wear; in fact, the wear patterns seem to be slow to even show up. I think I like the Melonite. The BCG cleans up pretty well with it, and the spring for the ejector was really clean in there. Good to go.