This Bear Creek Arsenal AR-15 24" heavy profile, 416R Stainless steel 5.56 NATO barrel has spiral flutes and has a rifle length gas system with a 1:8 twist. Use a Bear Creek Arsenal ar barrel in your AR15 next build and experience superior performance back by a lifetime warranty! 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 5.56 NATO 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