This BCA AR-15 Barrel is a 20" Government profile barrel made of 4150 chrome moly vanadium steel with a Black Nitride finish, a rifle length gas system with a 1:8 twist rate. The barrel is chambered in .223 Wylde and machined with M4 feed ramps in the barrel extension. All finished barrels go through a 100% inspection process. Inspections Equipment includes CMMs and Air Gauges for the bores as well as visual and machine inspection. Shop more .223 Wylde Barrels! {{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="42"}} Does not include gas block or gas tube It is the responsibility of the consumer to ensure all state, local, federal, and ITAR regulations are followed.