I have a Beta-C Mag for my .223 / 5.56 MM AR-15's, but it's a pain to use because of the Graphite. This system because of the way it is designed, doesn't require any. It also hold more rounds. I'm surprised this isn't more popular, especially with the full auto crowd. Admittedly it's use would be limited, and would weigh a ton when loaded and inserted into the rifle, but it sure would be FUN! Bill T.