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Questions & Answers
will this upper work on 5.56 lower Expert Answer

Yes, the Moriarti AR-15 10 inch .300 Blackout Upper Receiver is compatible with Milspec AR15 lower receivers.

by Ethan, Gear Expert, October 9, 2025
Caliber: .300 AAC Blackout Barrel Length: 10.5 inBarrel Profile: Medium Gas System Length: Pistol Length Barrel Twist Rate: 1-7 Threads per Inch: 5/8x24 Handguard Type: Free-Float Muzzle Device: A2 Flash Hider Finish: Hardcoat Anodized Color: Black/OD Green Gun Model: AR-15 Gas Block Journal Size-Diameter: .750 inHandguard Length: 10 in

Code: 5MY-UFH-N72AET-MAR-300-10-BLK-ODG-A2

MPN: MAR-300-10-BLK-ODG-A2

List: $399.95Save 10%
$359.99

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Product Info for Moriarti AR-15 10 inch .300 Blackout Upper Receiver with Flash Hider Assembly

Moriarti AR-15 300 Blackout Pistol Upper Assembly / 10 in Od Green M-lok / A2 is a perfect addition to your pistol look. Just drop this pistol upper assembly on your Mil-Spec lower receiver and enjoy the outdoors.image

WARNING: California`s Proposition 65

Specifications for Moriarti AR-15 10 inch .300 Blackout Upper Receiver with Flash Hider Assembly:

Manufacturer: Moriarti
Caliber: .300 AAC Blackout
Barrel Length: 10.5 in
Barrel Profile: Medium
Gas System Length: Pistol Length
Barrel Twist Rate: 1-7
Threads per Inch: 5/8x24
Handguard Type: Free-Float
Muzzle Device: A2 Flash Hider
Finish: Hardcoat Anodized
Color: Black/OD Green
Gun Model: AR-15
Fabric/Material: 7075-T6 Aluminum
Gas Block Journal Size-Diameter: .750 in
Handguard Length: 10 in
Gun Rail: M-LOK
Gun Make: AR Platform
Barrel Material: 4150 CMV Steel
Bolt Carrier Group Included: No
Charging Handle Included: No
Magazine Included: No
Mount Type: M-LOK

Package Contents:

  • Moriarti AR-15 10 inch .300 Blackout Upper Receiver with Flash Hider Assembly

Moriarti AR-15 10 inch .300 Blackout Upper Receiver with Flash Hider Assembly Orderable Models

List of Orderable Models

  • Moriarti Upper Receiver with Flash Hider, AR-15, .300 Blackout, 10.5 inch Barrel, Medium Profile, Pistol Length, 1x7 Twist, 5/8X24 Thread, M-LOK Handguard, A2 Flash Hider, Hardcoat Anodized, Black/ Od Green, MAR-300-10-BLK-ODG-A2 , MPN: MAR-300-10-BLK-ODG-A2 , Code: 5MY-UFH-N72AET-MAR-300-10-BLK-ODG-A2
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