Sons of Liberty Gun Works M4-L89 5.56 NATO Barreled Upper Receiver - 12.5"

The Sons of Liberty Gun Works M4-L89 12.5" Barreled Upper Receiver is built around a 5.56 NATO chambered 12.5” barrel with a carbine-length gas system and an A2 flash hider. The barrel is constructed from 4150 Chrome Moly Vanadium steel (per MIL-B-11595E), features a V2 profile, and is finished with a QPQ treatment for corrosion resistance. It’s button-rifled with a 1:7 twist for optimal performance.

Features:

• 12.5” barrel with A2 muzzle device
• 4150 Chrome Moly Vanadium steel barrel (MIL-B-11595E)
• QPQ corrosion-resistant barrel finish
• 5.56 NATO chamber, 1:7 twist, button rifled
• V2 barrel profile, MPI and HPT tested
• M4-style upper receiver made of 7075-T6 aluminum
• 11.75” L89 Drivelock M-LOK handguard

The upper receiver is made from 7075-T6 aluminum with a Type III hardcoat anodized finish and R5 Bright Dip treatment for added durability. T-mark engravings provide quick accessory placement reference. The 11.75” L89 Drivelock M-LOK rail is secured by a titanium barrel nut and offers seven-sides of M-LOK slots for flexible mounting options, dual limited-rotation QD sling sockets, and enhanced ventilation beneath the top rail.