Diamondback DB 6.5 Grendel Vanadium Steel Rifle Barrel - 18in - Black Nitride - The Diamondback Firearms 6.5 Grendel Barrel is a premium rifle barrel designed for precision and reliability. Featuring an 18in length and a 1: 8 twist rate, this barrel is optimized for AR rifles, offering excellent performance for a variety of shooting applications. Constructed from 4150 Chrome Moly steel with a black nitride finish, it ensures durability and corrosion resistance. The mid-length gas system and medium contour/profile make it a versatile and high-performing choice. 1:8 Threaded Barrel: 5/8 x 24 Button Rifled 5R Rifling M4 Feed Ramps Chrome Moly Vanaidum Steel Midlength Medium Profile