M4-89 5.56x45 NATO Assembled Upper Receiver - M4-89 5.56x45 NATO 12.5" Bbl 11.5" M89 Rail W/A2 Flash Hider
All Sons of Liberty Gun Works upper receivers
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Sons of Liberty Gun Works
Overview
The M4-89 assembled upper receiver from Sons of Liberty Gun Works is designed for the AR-15 platform and features a 12.5-inch barrel chambered in 5.56 NATO. This complete upper assembly simplifies the build process, allowing builders to easily attach it to their lower receiver for a compact yet versatile firearm. This upper receiver is commonly used in builds aimed at close-quarters engagements, where maneuverability and rapid handling are essential.
Specifications
M4-89 5.56x45 NATO Assembled Upper Receiver - M4-89 5.56x45 NATO 12.5" Bbl 11.5" M89 Rail W/A2 Flash Hider
Price and stock
The Sons of Liberty Gun Works M4-89 5.56x45 NATO Assembled Upper Receiver - M4-89 5.56x45 NATO 12.5" Bbl 11.5" M89 Rail W/A2 Flash Hider was out of stock everywhere we track for all of September 2026, and today none of the 2 retailers we track has it in stock right now. Listed prices start at $855 at Brownells for when it comes back.
Prices checked · refreshed daily across 37 retailers
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