{"product_id":"tacfire-bu45acp4-45-acp-4-ar-15-complete-upper-black-nitride","title":"TacFire BU45ACP4 .45 ACP 4\" AR-15 Complete Upper - Black Nitride","description":"\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe \u003cstrong\u003e\u003cspan style=\"background-color: #ffff00;\"\u003eTacFire BU45ACP4\u003c\/span\u003e\u003c\/strong\u003e is a complete \u003cstrong\u003e\u003cspan style=\"background-color: #ffff00;\"\u003e.45 ACP\u003c\/span\u003e\u003c\/strong\u003e upper assembly built around a compact \u003cstrong\u003e4\" black nitride\u003c\/strong\u003e barrel. The slow \u003cstrong\u003e1:16\u003c\/strong\u003e rifling twist is matched to heavy .45 ACP projectiles for reliable stabilization, and the muzzle is threaded \u003cstrong\u003e5\/8x24\u003c\/strong\u003e for compensator, suppressor, or other muzzle-device fitment.\u003c\/span\u003e\u003c\/p\u003e\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003eThe receiver is machined from \u003cstrong\u003e7075-T6 aluminum\u003c\/strong\u003e and finished in black anodize, topped with a full-length \u003cstrong\u003ePicatinny rail\u003c\/strong\u003e for optics, red dots, and back-up iron sights. A free-float \u003cstrong\u003eM-LOK\u003c\/strong\u003e handguard keeps the barrel unobstructed for consistent accuracy while providing a slim, modular platform for lights, lasers, and foregrips. A dedicated \u003cstrong\u003e.45 ACP bolt carrier group\u003c\/strong\u003e is included, so the upper drops onto any standard AR-15 lower and is ready to run.\u003c\/span\u003e\u003c\/p\u003e\u003cp\u003e\u003cspan style=\"font-size: 14pt;\"\u003ePurpose-built for \u003cstrong\u003epistol-caliber AR builds\u003c\/strong\u003e, the BU45ACP4 is a natural fit for short-barreled rifle, AR pistol, and PCC configurations chambered in .45 ACP. This listing is for the \u003cstrong\u003eupper only\u003c\/strong\u003e - a lower receiver, magazine, rear sight, and muzzle device are not included.\u003c\/span\u003e\u003c\/p\u003e","brand":"TacFire","offers":[{"title":"Default Title","offer_id":55044543709506,"sku":"173999","price":300.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0997\/7921\/5682\/files\/hires_a4a66f46-a258-456f-b13d-89fe809e4943.png?v=1784695558","url":"https:\/\/centerfiresystems.com\/products\/tacfire-bu45acp4-45-acp-4-ar-15-complete-upper-black-nitride","provider":"Centerfire Systems","version":"1.0","type":"link"}