The picture in the link is exactly what I've got. I thought it was something done in a machine shop since I could see faint marks around the area in question.
I have notice my gas key has a little movement; rings should still be good after changing them about 1,000 rounds ago.
I had looked on the other website you referenced, but did not look hard enough. Thanks for the reply and for the link.
Last edited by Kansas Shooter; October 18, 2012 at 08:35 AM.