{"product_id":"spikes-stu5025m4s-complete-upper-5-56x45mm-nato-16-1-7-black-phosphate","title":"Spikes STU5025M4S Complete Upper 5.56x45mm NATO 16\" 1:7 Black Phosphate","description":"\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe \u003cstrong\u003e\u003cspan style=\"background-color: #ffff00;\"\u003eSpikes STU5025M4S\u003c\/span\u003e\u003c\/strong\u003e is a complete \u003cstrong\u003eAR-15\/M4-pattern\u003c\/strong\u003e upper receiver assembly chambered in \u003cstrong\u003e\u003cspan style=\"background-color: #ffff00;\"\u003e5.56x45mm NATO\u003c\/span\u003e\u003c\/strong\u003e, offered as a turnkey replacement upper ready to mate with any standard mil-spec AR-15 lower.\u003c\/span\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eAt its core is a \u003cstrong\u003e16\"\u003c\/strong\u003e mil-spec \u003cstrong\u003echrome moly\u003c\/strong\u003e barrel cut to a classic \u003cstrong\u003eM4 carbine profile\u003c\/strong\u003e with a \u003cstrong\u003e1:7\u003c\/strong\u003e rifling twist, well suited to stabilizing a broad range of 5.56mm projectile weights. The barrel wears a \u003cstrong\u003eblack phosphate\u003c\/strong\u003e finish for corrosion resistance and is paired with a \u003cstrong\u003ecarbine-length gas system\u003c\/strong\u003e for reliable cycling. An \u003cstrong\u003eF-marked A2 front sight base\u003c\/strong\u003e with A2 front sight post is pinned in place.\u003c\/span\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe upper receiver is machined from \u003cstrong\u003e7075-T6 aluminum\u003c\/strong\u003e and finished in \u003cstrong\u003eblack\u003c\/strong\u003e. A black \u003cstrong\u003eM4 double head shield handguard\u003c\/strong\u003e rounds out the assembly with the familiar slim profile that accepts standard M4-pattern accessories. The complete upper ships ready to install on a mil-spec AR-15 lower (lower not included).\u003c\/span\u003e\u003c\/p\u003e","brand":"Spikes","offers":[{"title":"Default Title","offer_id":55002339213634,"sku":"99730","price":798.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0997\/7921\/5682\/files\/hires_66938949-fb12-449d-886f-d8071b092d2a.png?v=1784528707","url":"https:\/\/centerfiresystems.com\/products\/spikes-stu5025m4s-complete-upper-5-56x45mm-nato-16-1-7-black-phosphate","provider":"Centerfire Systems","version":"1.0","type":"link"}