The AAC 83 headstamp in 5.56×45 and 7.62×51 was a made by Igman of Yugoslavia for Nordac Manufacturing Corp. (NMC) in Fredericksburg, Virginia, and the initials stand for “American Armaments Corporation”. This was a deceiving contract intended for El Salvador.
D B on the Stewart headstamp is for Dave Brooks, who ordered these from the late Ken Stewart