I built this entirely myself. It is a .300 Blackout with a Wilson Combat SS Fluted barrel and BCE BABC 7.62 comp. The barrel pictured is 16", 18" OAL with the comp. The barrel is getting cut to 14" and the comp is getting pinned and welded, like, right now. Being a 13" rail it should help with overall balance. Heavy gun. Trying to shave weight now and the UBR isn't helping a damn thing. Oh well. Good thing I go to the gym or this would be difficult to swing.