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Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver MAR-300-6-A2 Caliber: .300 AAC Blackout, Barrel Length: 6 in, 13% Off w/ Free S&H

Moriarti AR-15 300 Blackout 6in Modular Pistol Upper Assembly, Hybrid M-LOK, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2
Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver, Medium, Pistol Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2
Moriarti AR-15 300 Blackout 6in Modular Pistol Upper Assembly, Hybrid M-LOK, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2
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Moriarti AR-15 300 Blackout 6in Modular Pistol Upper Assembly, Hybrid M-LOK, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2
Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver, Medium, Pistol Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2
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Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver, Medium, Pistol Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2

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Questions & Answers
Caliber:
.300 AAC Blackout
Barrel Length:
6 in
Barrel Profile:
Medium
Gas System Length:
Pistol Length
Barrel Twist Rate:
1-7
Muzzle Device:
A2 Flash Hider
Finish:
Nitride
Color:
Black
Gun Model:
AR-15
Gas Block Journal Size-Diameter:
.750 in
Handguard Length:
5.5 in
Weight:
56 oz

Code: 5MY-UFH-ABVW-MAR-300-6-A2

MPN: MAR-300-6-A2

UPC: 799787099306

List: $379.95Save 13%
$329.99

ATTENTION! We currently do not ship this product to P.O. Boxes, AK, CA, CT, DE, HI, MA, NJ, NY, U.S. Territories, or select Colorado locations. Please see our policies for more information or a detailed list of locations.

Product Info for Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver

Upgrade your AR-15 with this high-performance 300 Blackout pistol upper assembly for optimized accuracy, reliability, and modular customization. Perfect for tactical, sport shooting, or hunting enthusiasts.image

WARNING: California`s Proposition 65

Specifications for Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver:

Manufacturer: Moriarti
Caliber: .300 AAC Blackout
Barrel Length: 6 in
Barrel Profile: Medium
Gas System Length: Pistol Length
Barrel Twist Rate: 1-7
Muzzle Device: A2 Flash Hider
Finish: Nitride
Color: Black
Gun Model: AR-15
Fabric/Material: 4150 Chrome Moly Vanadium
Gas Block Journal Size-Diameter: .750 in
Handguard Length: 5.5 in
Gun Rail: M-LOK
Gun Make: AR Platform
Weight: 56 oz
Magazine Included: No
Threads per Inch: 5/8x24

Features of Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver

  • Chambered in 300 Blackout, offering superior ballistic performance. 1:7 RH twist ensures stable, consistent shots with a variety of bullet weights. 5/8x24 thread for versatile muzzle device compatibility. .750 diameter under the gas block and finished with an A2 flash hider in nitride and a crush washer. Equipped with M4 feedramps for reliable feeding
  • High-Quality Upper Receiver: A3 flat top upper receiver forged from top-tier 7075-T6 aluminum for strength and precision. Black hardcoat anodized for enhanced corrosion resistance. Includes forward assist and dust cover pre-installed. M4 feedramps ensure optimal reliability
  • Efficient Gas System: 750 low-profile gas block made from durable steel with a black hardcoat anodized finish. Designed for pistol-length gas system, ensuring smooth and reliable cycling for your 300 Blackout platform
  • Lightweight, Slim MLOK Rail: 5.5 in MLOK hybrid slim profile handguard crafted from aircraft-quality aluminum and black hardcoat anodized for superior durability and weight savings. Provides a modular platform for your accessories and enhances ergonomics
  • Compatibility and Versatility: Please note, BCG (bolt carrier group) and charging handle are not included

Package Contents:

  • Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver

What firearm models does the manufacturer say Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver is compatible with?

The manufacturer suggests that Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver is compatible with AR-15

Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver Orderable Models

List of Orderable Models

  • Moriarti AR-15 .300 AAC Blackout, 6 inch Upper Receiver, Medium, Pistol Length, 1-7 Twist, 5/8x24, A2 Flash Hider, Nitride, Black, MAR-300-6-A2 , MPN: MAR-300-6-A2 , UPC: 799787099306 , Code: 5MY-UFH-ABVW-MAR-300-6-A2
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Last updated 2026-09-17 UTC.