Four years ago I bought a CMMG AR-15 at an auction. The auctioneer said it was brand new, never fired, but had no papers or a box. I bought it cheap and it went into my son?s safe. It looked good and I bought it cheap.

Last weekend I mounted a red dot sight and took it on a try out. The rifle shot good, zeroed out it was going fine and functioning flawlessly. I wanted to switch from factory green tips (SS-109 NATO) to reloads I pulled the magazine tried to eject a live round. No way!!! It was stuck. Beating the charging handle with a boot heel finally did the trick. I cycled another round into the chamber and it fired and ejected but the following round could not be cycled by using the charger handle.

The chamber looks fine and I am stumped. A fired round ejects normally. A unfired round that is chambered by a fired round cannot be cycled. A manually chambered round is difficult but one chambered by firing a round has to be beat.

I?m guessing polishing the chamber might help. Any more guesses out there?