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Sons of Liberty Gun Works L89 Barreled AR-15 Upper Receiver - 5.56 - 14.5" - No Muzzle Device

SKU: U-M4L89-556-145-NMD
MPN: U-M4L89-556-145-NMD
Manufactured by Sons of Liberty Gun Works

Standard orders will ship out 2 business days if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination.

Details

The Sons of Liberty Gun Works L89 Barreled AR-15 Upper Receiver in 5.56 NATO builds on the EXO3 platform with the Drivelock barrel nut, integral steel QD cups, and an internal dowel pin between upper and rail — a more rigid 14.5" build for duty operators running lasers or VAS systems.

Features:

  • 14.5" Liberty Fighting Barrel chambered in 5.56 NATO
  • Mid-length-length gas system with 4140 steel gas block, nitrided gas tube
  • Forged mil-spec upper receiver
  • 13.75" L89 M-LOK handguard, seven-sided, Drivelock barrel nut
  • Integral steel QD cups at the barrel nut, both sides
  • Internal dowel pin between upper receiver and rail
  • Muzzle ships bare-threaded with no muzzle device installed, letting you choose your own
  • Test fired before shipment
  • Bolt carrier group and charging handle not included



The Drivelock barrel nut gives more consistent, repeatable torque than a standard barrel nut, and the internal dowel pin locks the handguard's position independent of the barrel nut alone — together minimizing the point-of-impact shift that rail-mounted lasers and VAS systems can otherwise introduce. Integral steel QD cups on both sides give hardened sling attachment without a separate socket.

Because this 14.5" barrel ships bare-threaded with no muzzle device, it must be built into an NFA-regulated short-barreled rifle or AR pistol rather than a standard rifle.

Sons of Liberty Gun Works builds and test-fires every rifle and barreled upper in the United States, applying the same standards to individual components as they do to their complete rifles.

Specifications

Barrel Coating
Barrel Length14.5
BrandSons of Liberty Gun Works
Caliber Gauge5.56 NATO
ColorBlack
FinishHardcoat Anodized
Gas System TypeDirect Impingement
Handguard13.75 in Freefloat Rail
PlatformAR-15
Thread Pattern1/2 X 28