AR-15 5.56 NATO 5" Micro ARP Pistol Upper – Blue Accent

5-inch 5.56 NATO Micro ARP

AR-15 5.56 NATO 5" Micro ARP Pistol Upper – Blue Accent

The Moriarti AR-15 5.56 NATO 5" Pistol Upper combines compact Micro ARP styling with distinctive blue accents for a build that stands out. Designed around a 5-inch 5.56 NATO black nitride barrel, this compact ARP upper delivers a lightweight and maneuverable configuration for custom AR pistol projects. The assembly uses a 5" medium-profile 4150V steel barrel with a black nitride finish, 1:5 twist rate, and 5R rifling. Its micro-length gas system incorporates a .750" gas block.

A forged 7075-T6 aluminum upper receiver is paired with a 4" black M-LOK handguard. Blue accent components include the forward assist, dust cover, charging handle, and aluminum can-style muzzle component.

Key Features

• 5" medium-profile 4150V steel barrel

• 1:5 twist rate with 5R rifling

• Black nitride barrel finish

• Micro-length gas system

• .750" gas block diameter

• Forged 7075-T6 aluminum upper receiver

• 4" black M-LOK handguard

• Blue forward assist and dust cover

• Blue charging handle included

• Blue aluminum can-style muzzle component

• 1/2×28 muzzle threads

• Optional bolt carrier group

Specifications

Specification	Value
Manufacturer	Moriarti Armaments
Product Code	MAR-556-5-BLUECAN
Series	Micro ARP
Platform	AR-15
Product Type	Pistol Upper Assembly
Caliber	5.56 NATO
Barrel Length	5"
Barrel Profile	Medium
Barrel Material	4150V Steel
Barrel Finish	Black Nitride
Barrel Twist	1:5
Rifling	5R
Barrel Weight	12 oz.
Gas System	Micro-Length
Gas Block Diameter	.750"
Muzzle Threads	1/2×28
Upper Receiver	Forged 7075-T6 Aluminum
Handguard	4" Black M-LOK
Accent Color	Blue
Forward Assist	Blue
Dust Cover	Blue
Charging Handle	Blue, Included
Muzzle Component	Blue Aluminum Can-Style Component
Bolt Carrier Group	Optional; Not Included by Default

Package Includes

• One assembled 5" 5.56 NATO upper receiver assembly

• Installed 5" medium-profile barrel

• Installed micro-length gas system

• 4" black M-LOK handguard

• Blue forward assist and dust cover

• Blue charging handle

• Blue aluminum can-style muzzle component

Not included: Bolt carrier group unless selected as an option, lower receiver, magazine, or sights unless separately specified.

FAQ

What is the barrel twist rate?

The barrel features a 1:5 twist rate with 5R rifling.

Does the upper include a charging handle and bolt carrier group?

The blue charging handle is included. The bolt carrier group is optional and is not included by default.

Is the 12 oz. weight for the complete upper assembly?

No. The stated 12 oz. weight is the barrel weight, not the weight of the assembled upper.

Product Image Notice

Images may not be the exact representation of the product.

What is a Micro ARP upper?

A Micro ARP upper is a compact AR pistol upper assembly built around a very short barrel and handguard configuration. This Moriarti model uses a 5" 5.56 NATO barrel, creating the compact profile commonly associated with Micro ARP, mini ARP, and AR pistol builds.