Fierce Firearms C3 Carbon Fiber Barrel 6.5mm Caliber 22in 1-8 Twist 5/8x24 Thread. Specifications for Fierce Firearms C3 Carbon Fiber Barrel: Manufacturer: Fierce Firearms Finish: Carbon Fiber Barrel Material: 416R Stainless Steel Barrel Profile: Straight Threads per Inch: 5/8x24 Gun Make: Universal Gun Model: Universal Features of Fierce Firearms C3 Carbon Fiber Barrel Match Grade Stainless Steel barrel liner Hand lapped Target Crown 5/8-24 TPI finish + Thread cap Matrix C3 Carbon Fiber wrap Package Contents: Fierce Firearms C3 Carbon Fiber Barrel What firearm models does the manufacturer say Fierce Firearms C3 Carbon Fiber Barrel is compatible with? The manufacturer suggests that Fierce Firearms C3 Carbon Fiber Barrel is compatible with UniversalFierce Firearms 651822: C3 Carbon Fiber Barrel 6.5mm Caliber 22in 1-8 Twist 5/8x24 Thread