Sons of Liberty Gun Works M4-L89 URG 14.5″ 5.56 NATO Upper Receiver Group with ASR Muzzle Device

The Sons of Liberty Gun Works (SOLGW) M4-L89 URG is a precision-built upper receiver group engineered for serious shooters who demand reliability, accuracy, and mission-ready performance. Chambered in 5.56 NATO with a 14.5″ barrel, this URG is permanently pinned and welded (P/W) with an ASR muzzle device to achieve legal 16″ overall barrel length — no NFA paperwork required.

Built around a forged upper receiver and SOLGW’s signature L89 7-sided M-LOK handguard rail system, this upper offers a rugged, streamlined platform with versatile accessory mounting options. The 14.5″ Liberty Fighting Barrel delivers outstanding velocity, balance, and handling in a compact, maneuverable package — ideal for competition, home defense, law enforcement, or tactical use.

**Key Features:**
– Chambered in 5.56 NATO
– 14.5″ Liberty Fighting Barrel, permanently pinned and welded with ASR muzzle device
– L89 7-sided M-LOK handguard rail
– Forged upper receiver
– Mil-spec compatible components
– ASR (Advanced Small Arms Retention) muzzle device
– No lower included — pairs with any mil-spec lower receiver

Sons of Liberty Gun Works has built a strong reputation among competitive shooters, military personnel, and firearms enthusiasts for producing no-compromise, American-made components. Whether you’re completing a custom build, upgrading your existing platform, or adding a battle-ready upper to your collection, the SOLGW M4-L89 URG delivers the quality and craftsmanship you expect.

Available online at DeepRootsRifleCo.com with fast shipping nationwide, or stop by our Eustis, Florida gun store to see our full selection of SOLGW products. Our knowledgeable staff is ready to help you find the right upper, build out your rifle, or answer any questions.