Sons of Liberty Gun Works M4-L89 5.56mm 14.5" Bbl Mid Gas L89 Rail No Muzzle Device Liberty Fighting Bbl & Mil-Spec Upper Receiver U-M4L89-556-145-NMD

The Sons of Liberty Gun Works M4-L89 Barreled Upper is a duty-grade, mid-length upper receiver group designed for shooters who want to select their own muzzle device for a custom build or a permanent pin-and-weld application. It features a 14.5-inch Liberty Fighting Barrel (4150 CrMoV) with a mid-length gas system, providing a smoother recoil impulse and improved parts longevity compared to shorter systems. The core of this assembly is the L89 Drivelock handguard, which utilizes a titanium barrel nut and a specialized three-point locking mechanism to ensure that the rail remains perfectly indexed and rigid, making it an ideal platform for holding a precise zero with lasers and night vision equipment. As an "NMD" (No Muzzle Device) variant, the 1/2x28 threads are left bare, offering total flexibility for suppressor mounts or compensators.