Noveske SPR Barrel Features The Noveske SPR barrel is machined from 416R stainless steel with a 1:7 twist rate built for shooters chambering 5.56 NATO who want the extended range and velocity advantages of an 18 inch barrel. Its Extra Thicc contour carries Noveske s disruptive deep fluting removing weight and increasing surface area for heat dissipation while retaining the rigidity needed for precision shooting. Each barrel is fitted with a hand-polished proprietary Noveske match chamber and extended hand-polished feed ramps both aimed at improving feeding reliability and reducing chamber-related accuracy variation. The rifle-length gas system this barrel uses is tuned for the longer barrel providing a smoother recoil impulse than shorter gas systems would allow at this length. A pinned .936 inch low-profile gas block keeps gas timing consistent shot after shot an important factor for shooters relying on this barrel for designated marksman style precision work. The bead-blasted silver finish resists heat discoloration through sustained firing strings while giving the barrel a distinct non-anodized appearance. A headspaced bolt is included to simplify the build process for customers assembling their own upper receiver around this barrel. Threaded 1/2x28 for standard AR-15 muzzle devices the Noveske SPR barrel gives precision-minded builders a fluted lightweight option for extended-range 5.56 NATO work. Noveske SPR Barrel Specifications Manufacturer: Noveske Model: SPR Type: Barrel Caliber: 5.56 NATO Compatible Hosts: AR-15 Barrel Length: 18 Barrel Material: 416R Stainless Steel Barrel Finish: Bead Blasted Color: Silver Twist Rate: 1:7 Thread Pitch: 1/2x28 Gas System: Rifle Length Barrel Description: Disruptive Deep Fluting Accessories Included: Pinned Gas Block Headspaced Bolt Available At: GrabAGun