Solgw M4-89 16" 300blk Urg

The Solgw M4-89 16" 300blk Urg upper receiver assembly delivers a purpose-built platform for shooters who demand quiet, subsonic performance in a compact form factor. Sons of Liberty Gun Works engineered this 16-inch upper for .300 Blackout ammunition, making it ideal for home defense, tactical training, and suppressed shooting applications where velocity control and noise reduction are priorities. The URG designation signals a complete upper receiver group—ready to pair with your lower receiver for a fully functional rifle build.

Built with the precision and durability Sons of Liberty is known for, this upper features a 16-inch barrel optimized to stabilize .300 Blackout subsonic rounds while maintaining a manageable profile. The M4 platform design ensures compatibility with standard AR-15 lower receivers and integrates with existing mil-spec components. At 4.25 pounds, the assembly strikes a balance between structural rigidity and shooter control, reducing fatigue during extended shooting sessions or tactical drills. The compact 30.25-inch overall length makes the Solgw M4-89 suitable for confined spaces and vehicle storage without sacrificing ballistic performance.

This upper is best suited for experienced AR-15 builders and shooters transitioning to subsonic .300 Blackout platforms, particularly those running sound suppressors for hearing protection and tactical discretion. Installation requires only a properly assembled AR-15 lower receiver—no gunsmithing necessary. Whether you're building a dedicated suppressed rifle, expanding your caliber options, or developing a short-range precision setup, the Solgw M4-89 16" 300blk Urg provides the quality foundation Sons of Liberty customers expect and the performance subsonic shooting demands.