{"product_id":"luth-ar-ftbl-b20m-223-rem-20-fluted-bull-barrel-complete-upper-assembly","title":"Luth-AR FTBL-B20M .223 Rem 20\" Fluted Bull Barrel Complete Upper Assembly","description":"\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe \u003cstrong\u003e\u003cspan style=\"background-color: #ffff00;\"\u003eLuth-AR FTBL-B20M\u003c\/span\u003e\u003c\/strong\u003e is a complete \u003cstrong\u003e20\" fluted bull barrel\u003c\/strong\u003e upper assembly chambered in \u003cstrong\u003e.223 Remington\u003c\/strong\u003e. Designed to drop onto any mil-spec AR-15 lower receiver, this upper ships with the A3 flattop upper receiver, charging handle, and bolt carrier group already installed and headspaced.\u003c\/span\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe barrel is machined from \u003cstrong\u003e416 stainless steel\u003c\/strong\u003e in a heavy \u003cstrong\u003ebull profile\u003c\/strong\u003e with fluting, and features a \u003cstrong\u003e1:9 twist\u003c\/strong\u003e rate. The added material of the bull profile gives the complete assembly a substantial weight of approximately \u003cstrong\u003e6.8 lbs\u003c\/strong\u003e, and Luth-AR markets this upper as a \u003cstrong\u003eprecision-shooting\u003c\/strong\u003e configuration.\u003c\/span\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eInternally, the bolt is machined from \u003cstrong\u003eCarpenter 158 steel\u003c\/strong\u003e with the extractor in \u003cstrong\u003e4140 alloy steel\u003c\/strong\u003e, both \u003cstrong\u003eArmy-spec heat treated\u003c\/strong\u003e and finished in \u003cstrong\u003emanganese phosphate\u003c\/strong\u003e. The barrel carries a bare \u003cstrong\u003e416 stainless steel\u003c\/strong\u003e finish, while the bolt carrier group carries the \u003cstrong\u003emanganese phosphate\u003c\/strong\u003e coating. Built for the \u003cstrong\u003eAR-15 platform\u003c\/strong\u003e, this complete upper provides a turn-key upgrade for an existing lower receiver.\u003c\/span\u003e\u003c\/p\u003e","brand":"Luth-AR","offers":[{"title":"Default Title","offer_id":55082416963906,"sku":"196428","price":534.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0997\/7921\/5682\/files\/hires_acfca2e3-ae18-47af-b9f0-6a21ccbd71d1.png?v=1784765962","url":"https:\/\/centerfiresystems.com\/products\/luth-ar-ftbl-b20m-223-rem-20-fluted-bull-barrel-complete-upper-assembly","provider":"Centerfire Systems","version":"1.0","type":"link"}