Free Shipping & Free Returns*

FREE SHIPPING on Over 250,000 Products

Enjoy free shipping during the holidays! Shop now and get Free Value Shipping on most orders over $49 to the contiguous 48 states, DC and to all U.S. Military APO/FPO/DPO addresses.

Enjoy Our Extended FREE RETURNS

We want to ensure that making a return is as easy as possible! With our Hassle-Free, Extended Holiday Returns, eligible orders placed from November 12, 2025 on will benefit from an extended return deadline (January 13, 2026 or 30 days after receipt of your order - whichever is later). We'll even cover the cost of return shipping. Learn more about our Return Policy.

Shopping Cart
Government Export Restriction Government Export Restriction
Government Restriction Government Restriction
Questions & Answers
Caliber: 5.56x45mm NATO Barrel Length: 5 inBarrel Profile: Medium Gas System Length: Micro Barrel Twist Rate: 1-5 Threads per Inch: 1/2x28 Muzzle Device: A2 Flash Hider Finish: Nitride Gun Model: AR-15 Gas Block Journal Size-Diameter: .750 inHandguard Length: 4 in

Code: 5MY-UFH-MI01UR-MAR-556-4-A2

MPN: MAR-556-4-A2

List: $349.95Save 36%
$223.99

ATTENTION! We currently do not ship this product to AK, CA, HI, IL, NY, WA, P.O. Boxes, and U.S. Territories. Please see our policies for more information.

Product Info for Moriarti AR-15, 5.56x45mm NATO, 5 inch Upper Receiver

The MORIARTI AR-15 5.56 NATO 5 in Pistol Upper Assembly is precision-engineered for superior performance in a compact AR-15 pistol build. Featuring a 5-inch 4150 Chrome Moly Vanadium barrel with a nitride finish and a 1:5 twist rate, this upper is ready for your Suppressor and ensures exceptional durability and accuracy. The A3 flat top upper receiver comes equipped with a forward assist and dust cover for enhanced functionality. Paired with a 4 in MLOK handguard for versatility and modularity, this assembly is ready to take your AR build to the next level. Perfect for home defense or tactical use, this upper does not include a bolt carrier group (BCG) or charging handle, allowing you to customize your build to your preference.image

WARNING: California`s Proposition 65

Specifications for Moriarti AR-15, 5.56x45mm NATO, 5 inch Upper Receiver:

Manufacturer: Moriarti
Caliber: 5.56x45mm NATO
Barrel Length: 5 in
Barrel Profile: Medium
Gas System Length: Micro
Barrel Twist Rate: 1-5
Threads per Inch: 1/2x28
Muzzle Device: A2 Flash Hider
Finish: Nitride
Gun Model: AR-15
Fabric/Material: 4150 Chrome Moly Vanadium
Gas Block Journal Size-Diameter: .750 in
Handguard Length: 4 in
Gun Rail: M-LOK
Gun Make: AR Platform

Package Contents:

  • Moriarti AR-15, 5.56x45mm NATO, 5 inch Upper Receiver

Moriarti AR-15, 5.56x45mm NATO, 5 inch Upper Receiver Orderable Models

List of Orderable Models

  • Moriarti AR-15, 5.56x45mm NATO, 5 inch Upper Receiver, Medium, Micro Length, 1-5 Twist, 1/2x28, A2 Flash Hider, Nitride, MAR-556-4-A2 , MPN: MAR-556-4-A2 , Code: 5MY-UFH-MI01UR-MAR-556-4-A2
Compare (0)