TFBTV Shooting: The CMMG Mk-W Anvil in .458 SOCOM Posted July 21, 2016 in AR-15, Guns & Gear, TFBTV by James Reeves with 6 Comments In this episode of TFBTV Shooting: James shoots the monster of an AR15 made by CMMG, the Mk-W, a.k.a. the Anvil; a .458 SOCOM AR on a custom engineered platform from CMMG. Full review is here: https://youtu.be/-oYoBRYq2Rs