Diamondback Firearms DB15 rifle uses a gas-impingement system and high quality CNC machined components. Features a 4140 chrome moly barrel, A3 Flattop upper receiver, carbine length gas system, 12" M-LOK rail, MOE grip, A2 Flash hider muzzle and a Magpul MOE Carbine stock. Made in the USA. This model comes with a compatible upper assembly chambered for 300 Blackout. Oal 32.50"- 35.75" Hand Right Hand Twist 1:8" Action semi-auto Muzzle A2 Flash Hider Safety Manual Thumb Series Combo Sights Optic Ready Weight 6.65 lbs Caliber 300 blackout Capacity 30+1 Weight Range 6 lbs to 6.99 lbs Barrel Length 16" Receiver Material 7075-T6 Aluminum Stock Description Adjustable Magpul Carbine Barrel Description Chromoly Steel Stock Finish Group Black Barrel Length Range 16" to 16.99"