A couple years back, CMMG surprised the shooting community by launching its Mutant, a nifty little gas-impingement operated semi-automatic AR pattern rifle that was built around the 7.62x39 mm cartridge—which, as you probably know, is far more commonly associated with the AK-47. The Mutant got rave reviews from media members and consumers alike—even winning a Golden Bullseye Award from our sister publication, American Rifleman—which inspired the company to keep toying with the idea. The result is the rifle that became our latest episode of #SundayGunday, and is chambered in, of all things, .458 SOCOM: Meet the CMMG MkW Anvil. You can learn more about it in the video embedded above.