Fennek 5.56 NATO AR-15 Upper

This is a complete upper receiver assembly built for reliability and performance on the AR-15 platform. The Fennek upper pairs a 16.5-inch 4150 CrMoV barrel with a 15-inch M-Lok handguard, micro low-profile gas block, and all necessary components to function as a standalone upper assembly.

Key Features

• 16.5-inch 4150 CrMoV barrel with nitride finish and 1:7 twist rate
• 15-inch M-Lok handguard for modular accessory mounting
• Micro low-profile gas block with mid-length stainless steel gas tube
• 7075-T6 aluminum upper receiver with M4 feed ramps and anodized finish
• AR-15 complete bolt carrier group, charging handle, and forward assist included
• AR-15 1/2x28 GI birdcage flash hider with crush washer

Perfect For

• Builders seeking a complete upper assembly ready to pair with a lower receiver
• Shooters wanting a mid-length gas system for balanced recoil and reliability
• AR-15 enthusiasts building a 5.56 NATO rifle configuration
• Precision shooters who value barrel quality and accuracy potential

Barrel and Gas System

The 16.5-inch 4150 CrMoV barrel features a nitride finish for corrosion resistance and durability. The 1:7 twist rate stabilizes standard and heavier 5.56 NATO ammunition effectively. A mid-length stainless steel gas tube pairs with the micro low-profile gas block to cycle the action smoothly without excessive wear on components.

Handguard and Mounting

The 15-inch M-Lok handguard provides a modern mounting interface for tactical accessories, optics, lights, and grips. M-Lok slots are distributed along the handguard for flexible load distribution without unnecessary weight.

Upper Assembly Components

This complete upper includes a 7075-T6 aluminum upper receiver with M4 feed ramps, forward assist assembly, ejection port door with rod and spring, and charging handle. The bolt carrier group is machined from 9310 alloy steel with a nitride finish and is made in the USA. These components work together to cycle 5.56 NATO ammunition reliably.

What You Need to Know

This is a complete upper receiver assembly. A lower receiver is required to build a functional rifle. The included components support standard AR-15 lower receivers with mil-spec dimensions. The upper receiver features anodized aluminum construction, which provides durability and corrosion resistance without the weight of other finishes.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. BCG and charging handle are not included separately, as they ship with this complete upper. Lower receiver not included.