With similar exterior dimensions to most 30rd 5.56mm AR magazines, the CMMG 4.6x30mm magazine boasts 40 round capacity, and is designed to work with any AR15 lower receiver. Once you pair the lower of your choice and this magazine with a CMMG 4.6x30mm upper receiver, you're ready for range time. Designed exclusively to feed the 4.6x30mm cartridge.
