Luth-AR .223 Rem Fluted Threaded Bull Barrel 18 in Rifle 1-9 Twist 1/2 x 28 Silver. Putting extra weight forward a Bull Barrel helps minimize gun movement. The thicker barrel reduces barrel vibration and takes longer to heat up allowing more shots on target before accuracy starts to deteriorate. Specifications for Luth-AR .223 Rem Fluted Threaded Bull Barrel: Manufacturer: Luth-AR Color: Steel Silver Finish: Stainless Fabric/Material: Stainless Steel Caliber: .223 Remington Barrel Profile: Bull Threads per Inch: 1/2x28 Barrel Twist Rate: 1-9 Barrel Material: 416R Stainless Steel Flutes: Yes Gun Model: AR-15 Features of Luth-AR .223 Rem Fluted Threaded Bull Barrel Fluted Bull Barrel 416 SS. 6 Lands and Groves. M4 Feed Ramp. Button Broached. Package Contents: Luth-AR .223 Rem Fluted Threaded Bull Barrel What firearm models does the manufacturer say Luth-AR .223 Rem Fluted Threaded Bull Barrel is compatible with? The manufacturer suggests that Luth-AR .223 Rem Fluted Threaded Bull Barrel is compatible with AR-15Luth-AR BL-B18FT: .223 Rem Fluted Threaded Bull Barrel 18 in Rifle 1-9 Twist 1/2 x 28 Silver