Product DescriptionThe FN AR-15 barrel (MPN 36423) is a cold hammer forged, chrome-lined 18 inch barrel built from FN's proprietary Chrome Moly Vanadium steel for durability and consistent performance. Each barrel is magnetic particle tested for quality assurance, with a chrome-lined chamber and bore designed to resist corrosion and heat erosion for extended barrel life. M4-style feed ramps and the barrel extension promote reliable feeding, while a matte black manganese phosphate finish helps protect against external corrosion and oxidation. Designed for a rifle-length gas system and chambered in 5.56x45mm NATO, this barrel is a strong choice for AR-15 builds prioritizing longevity and reliability.Product Highlights Cold hammer forged (CHF) Chrome Moly Vanadium (CMV) steel construction for long-lasting durability Chrome-lined bore and chamber to improve corrosion resistance and reduce heat erosion Magnetic particle tested for added quality control and consistency M4-style feed ramps and barrel extension for dependable feeding Matte black manganese phosphate finish to resist external corrosion and oxidationSpecs Brand: FN Manufacturer Part Number: 36423 UPC: 845737005146 Platform: AR-15 Caliber: 5.56x45mm NATO Barrel Length: 18 in Gas System Length: Rifle length Material: Chrome Moly Vanadium (CMV) steel, cold hammer forged Bore/Chamber: Chrome lined Finish: Manganese phosphate (black phosphate) Feed Ramps: M4 style Twist Rate: 1:7 RH Muzzle Threads: 1/2 x 28 Gas Block Diameter: 0.750 inDisclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product's manufacturer.