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Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver MAR-300-5-4-A2 Caliber: .300 AAC Blackout, Barrel Length: 5 in, 34% Off w/ Free Shipping

Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver, Medium, Micro Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, MAR-300-5-4-A2
Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver, Medium, Micro Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, MAR-300-5-4-A2
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Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver, Medium, Micro Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, MAR-300-5-4-A2

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Questions & Answers
Customer Reviews
Most Recent Reviews
great micro supress friendly by kilop, Verified Owner, April 16, 2026
Small compact enough for home defense or truck gun
Read 1 Review

On Sale

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Caliber:
.300 AAC Blackout
Barrel Length:
5 in
Barrel Profile:
Medium
Gas System Length:
Micro
Barrel Twist Rate:
1-7
Firearms Threads Per Inch:
5/8x24
Muzzle Device:
A2 Flash Hider
Finish:
Nitride
Gun Model:
AR-15
Gas Block Journal Size-Diameter:
.750 in
Handguard Length:
4 in

Code: 5MY-UFH-MI02UR-MAR-300-5-4-A2

MPN: MAR-300-5-4-A2

UPC: 799787098897

On Sale
List: $349.95Save 34%
$229.99

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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, .300 AAC Blackout, 5 inch Upper Receiver

The Moriarti AR-15 300 Blackout 5 in Micro Pistol Upper Assembly is built for shooters who demand high performance in a compact platform. Engineered for suppressor compatibility, this upper features a durable 5-inch 4150 CMV barrel with a black nitride finish and a 1:7 twist rate to stabilize subsonic and heavier grain projectiles.image

Ideal for tactical builds or home defense, this short-barrel upper includes a slim 4-inch MLOK free-float handguard for maximum modularity, and an A2 flash hider to minimize muzzle flash. The A3 flat top upper receiver is made from billet aluminum, anodized to MIL-SPEC standards, and comes equipped with a forward assist and dust cover.

Note: This upper does not include a bolt carrier group (BCG) or charging handlegiving you the flexibility to complete your build as you prefer.

WARNING: California`s Proposition 65

Specifications for Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver:

Manufacturer: Moriarti
Caliber: .300 AAC Blackout
Barrel Length: 5 in
Barrel Profile: Medium
Gas System Length: Micro
Barrel Twist Rate: 1-7
Firearms Threads Per Inch: 5/8x24
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, .300 AAC Blackout, 5 inch Upper Receiver

What firearm models does the manufacturer say Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver is compatible with?

The manufacturer suggests that Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver is compatible with AR-15

Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver Orderable Models

List of Orderable Models

  • Moriarti AR-15, .300 AAC Blackout, 5 inch Upper Receiver, Medium, Micro Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, MAR-300-5-4-A2 , MPN: MAR-300-5-4-A2 , UPC: 799787098897 , Code: 5MY-UFH-MI02UR-MAR-300-5-4-A2
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