08-16-2011, 04:35 PM
If it is a new upper, are you running it sloppy wet with Break Free? I have seen this several time where guys have an existing upper that works fine with a medium amount of quality gun oil but then they can't understand why a new upper does not function well. I would make up 5 or 6 dummy rounds and lube the heck out of the bolt and carrier and manually cycle the dummy rounds through the upper until you have about 200 rounds cycled through.
