Magpul Industries Magazine, PMAG 10 5.56 AC, 223 Remington, 556NATO, 10 Round, Fits AICS Short Action, Black MAG1100-BLK The PMAG 10 5.56 AC is a polymer 5.56x45 NATO (.223 Remington) magazine designed for short action Accuracy International Chassis Systems (AICS)-pattern bottom metal" including the Bolt Action Magazine Well for the Magpul Hunter family of stocks.