Sons of Liberty Gun Works M4-L89 5.56 NATO Barreled Upper Receiver - 16" - No Muzzle Device

The Sons of Liberty Gun Works M4-L89 16" Barreled Upper Receiver is built for durability. It features a 16” 5.56 NATO barrel with a mid-length gas system. The barrel is made from 4150 Chrome Moly Vanadium steel, with a corrosion-resistant QPQ finish, V2 profile, and 1:7 twist for reliable performance.

The M4 upper is machined from 7075-T6 aluminum and finished with a Type III hardcoat anodizing and R5 Bright Dip. It includes T-mark engravings for easy accessory placement. The 15.25” L89 Drivelock M-LOK rail offers a titanium barrel nut, 7-sided M-LOK slots, dual steel QD sling sockets, and optimized cooling slots under the top rail—giving you ample space and flexibility for mounting accessories.

Note: These do not come with a muzzle device.

Features:

• 16” barrel with mid-length gas system
• V2 barrel profile, MPI and HPT tested
• 4150 Chrome Moly Vanadium steel barrel (MIL-B-11595E)
• QPQ corrosion-resistant barrel finish
• 5.56 NATO chamber, 1:7 twist, button rifled
• M4-style upper receiver
• 7075-T6 aluminum with Type III hardcoat anodizing and R5 Bright Dip
• Engraved T-marks for accessory alignment
• 15.25” L89 Drivelock M-LOK handguard

The M4 upper is machined from 7075-T6 aluminum and finished with a Type III hardcoat anodizing and R5 Bright Dip. It includes T-mark engravings for easy accessory placement. The 15.25” L89 Drivelock M-LOK rail offers a titanium barrel nut, 7-sided M-LOK slots, dual steel QD sling sockets, and optimized cooling slots under the top rail—giving you ample space and flexibility for mounting accessories.