The growing popularity of 300 BLK cannot be understated. The Spike's Tactical 16" 300 Blackout Complete Upper offers the same level of quality and performance available in all their rifles. Spike’s Tactical maintains a high standard of tolerances and attention to detail in the uppers they use for complete rifle builds. Every complete upper is test fired before leaving their facility and is backed by the Spike's Tactical lifetime warranty. Features: - 300 BLK 16" chrome lined, cold hammer forged barrel with phosphate coating. - 5/8x24 thread pitch with 1:7 twist rate.