This BCA AR-15 complete 12.7x42 rifle length upper has a 10.5" parkerized Heavy barrel, and features a 1:20 twist rate, with a pistol length gas system. It includes a 9.5" MLOK Rail, an M4 flat-top billet upper receiver, a BCA AR15 bolt carrier group, a flash hider, and a right-side charging (Gen2) handle (patent protected). This 12.7x42 is compatible with any mil-spec AR-15 lower.Shop more 12.7 x 42 Uppers!Magazine not included. Check out Magazines here!{{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="56"}}{{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="98"}}{{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="91"}}{{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="42"}}