Does that Muzzle brake come from the factory like that???..Please forgive me if this is a silly question I wasn't in the Military just the Air Force!
Ma Deuce does not have a muzzle brake. That saying is machined into the crown of the barrel.
That muzzle brake is standard now on the Sebu (IIRC) 50 cal bolt action. They also sell them as replacements for muzzle brakes on other brands of the 50 sniper rifles.
Dunno what it's doing in the sand box... Standard issue is the Barrett M82A2 a ten round semi auto 50 cal... That might belong to one of the "securty personel".