Our Rosco 5.56 (NATO) barrels are designed to meet the modern day carbine shooter’s requirements. We are a long way from our daddyâ€™s â€œSporterâ€ AR, and those specs just wonâ€™t cut it anymore. From properly managed dwell times for SBRâ€™s, to running Suppressed, or setting up a balanced patrol carbine we have incorporated your needs into our engineering. We have successfully accomplished this by picking the right twist rates, gas port diameters, and barrel materials according to the barrel we are making (not a lazy blanket method). We have also balanced input from our consumers and military end users in order to bring you the product you need, not just the one we want to sell you. Browse our high quality AR15, M4, and SBR barrels today!