Rock River Arms .458 Socom Upper with Muzzle Brake

I purchased about one year ago. I have never fired. This is a new upper with the only modification is a awesome looking muzzle brake. Robert9043073517 RRA technical Info:http: Rock River Arms 16" .458 SOCOM CAR A4 Complete Upper Half Offering the ultimate combination of firepower and flexibility, the .458 SOCOM upper half works with standard AR lower receivers and unmodified 30 round GI mags. .458 SOCOM ammunition is available in a wide variety of loads and bullet types, with sub-sonic to high velocity performance, and delivers to the AR platform unprecedented terminal ballistics and stopping power. .458 SOCOM ammunition is available in a variety of factory loads from SBR Ammunition. Includes Bolt Carrier Group and Charging Handle Assembly Caliber: .458 SOCOM Chamber Upper Receiver: Forged A4 Barrel: 16" Chrome Moly Bull Barrel, 1:14 Twist Muzzle Device: REPLACED WITH MUZZLE BRAKE Gas Block: Varmint Gas Block with Sight Rail Handguard: RRA Aluminum Free Float Tube, CAR Length