In aluminum 'mag bodies, the bolt spring contacts the inside of the body on a ledge just behind the feed neck area. If unprotected, this aluminum ledge will eventually peen out and cause problems. The ring protects the aluminum ledge from the bolt spring, and the clip keeps the ring from falling out when the valve and bolt are removed from the body.
The Karta from Deadlywind is a fully sculptured, 4-axis CNC milled aluminum body/rail kit for the Automag. We start with authentic, AGD factory spec'd aluminum "Slug" body and AGD body rails. Starting with these components ensures that all our bodies will work 100% with AGD equipment... no tollerance or QC issues with these beauties!