300 Blackout Pistol Upper Assemblies
300 Blackout Pistol Upper Assemblies
Achieve superior shooting results by boosting the performance of your rifle with Moriarti Armaments' 300 Blackout Upper series. With a variety of configurations available, whether you prefer a pistol or carbine length, our 300 BLK uppers are designed to deliver unparalleled precision and reliability.
Can I switch between 5.56 and 300 Blackout?
Yes. Because both cartridges use the same AR-15 lower receiver, you can switch calibers by changing the complete upper receiver. Always verify the correct ammunition is used with the installed upper to avoid potentially dangerous caliber mix-ups.
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4.5" Micro ARP Upper Assembly – 5.56, .300 BLK, 7.62×39 & .338 ARC | Mini Can
The Moriarti 4.5" Micro ARP Upper Assembly with Mini Can is a compact AR-15 upper configuration avai..
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5" 300 Blackout Upper Assembly – AR-15 Pistol Upper with American Flag Engraving & Shark Muzzle Brake | Moriarti Armaments
Upgrade your AR-15 platform with the Moriarti 5 Inch 300 Blackout Upper Assembly, designed for shoot..
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5" AR-15 Suppressor Ready Pistol Upper Assembly – Choose Caliber & Color
The Moriarti 5" AR-15 Suppressor Ready Pistol Upper Assembly is available in 5.56 NATO, .300 AAC Bla..
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AR-15 300 Blackout 5" Centurion Upper Assembly / MLOK – Choose Handguard Color
Unleash compact performance with the Moriarti 5 Inch 300 Blackout Pistol Upper Assembly – Centurion ..
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AR-15 300 Blackout 5" Micro Upper Assembly / Sound Forwarder / Mlok / 1x7
Upgrade your AR-15 build with this 300 Blackout 5" Nitride Upper Assembly from Moriarti Armaments, d..
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AR-15 300 Blackout 5" PISTOL BILLET UPPER / 4'' MLOK / GOLD MUZZLE / CH
AR-15 300 Blackout 5" PISTOL BILLET UPPER / 4'' MLOK / GOLD MUZZLE BRAKE FEATURES:300 Blackout 5 Inc..
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AR-15 300 BLACKOUT 5'' PISTOL BILLET UPPER / CH / 4'' MLOK / STAY SPOOKY- COLOR SET
Moriarti Armaments introduces the Stay Spooky 300 Blackout Pistol Upper, a compact, lightweight, and..
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AR-15 300 BLK 5" Pistol Hybrid Upper Assembly, Spitfire Muzzle, Mlok Handguard, Zombie Green – Moriarti Arms
Elevate your build with the AR-15 300 BLK 5" Pistol Hybrid Upper Assembly in Zombie Green, precision..
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AR-15 300 BLK 5" Pistol Upper Assembly - Gold Spitfire / Mlok
Unleash precision, power, and performance with the AR-15 300 Blackout 5" Pistol Upper Assembly featu..
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Micro ARP 300 Blackout 5" Complete Upper Assembly | AR-15 Pistol Upper | Suppressor Ready | Moriarti Armaments
The Moriarti Micro ARP 300 Blackout Upper Assembly is designed for shooters looking for a compact, v..
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Micro ARP AR-15 300 Blackout 5" Hybrid Complete Upper Assembly | Spitfire Flash Can | M-LOK | Moriarti Armaments
Build the ultimate Micro ARP with the Moriarti AR-15 300 Blackout 5" Hybrid Complete Upper Assembly...
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Moriarti Armaments AR-15 300 Blackout 5" Cookie Cutter Upper Assembly
Elevate your shooting experience with the Moriarti Armaments 300 Blackout 5" Cookie Cutter Upper Ass..
RADIAN UPPER 9
The Radian Weapons is a complete upper receiver in 300 Blackout with a 9" barrel. Key details Bran..
RADIAN UPPER 9
The Radian Weapons is a complete upper receiver in 300 Blackout with a 9" barrel. Key details Bran..
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7.5" .300 AAC Blackout AR-15 SBR-Ready Kit – Compression Series
The Moriarti Armaments 7.5" .300 AAC Blackout Compression Series SBR-Ready Kit features a 7.5" barre..
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AR-15 300 Blackout 6" Modular Pistol Upper Assembly / Hybrid Mlok / A2
AR-15 300 Blackout 6" Modular Pistol Upper Assembly | Hybrid MLOK | A2 Flash HiderFeatures:Premium B..
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AR-15 7.5" Pistol Upper Assembly | Choose Caliber | Gradient Cerakote Finish | Premium Performance
Elevate your AR-15 build with this 7.5" Pistol Upper Assembly designed for both style and functional..
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7.5" AR-15 Cookie Cutter Upper – 5.56 NATO, 300 BLK & 7.62x39
Give your AR-15 a distinctive look with the Moriarti 7.5" Cookie Cutter Upper Assembly, featuring th..
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AR-15 300 Blackout 10.5" Complete Upper Assembly | Diamond Cut M-LOK | Burnt Bronze Cerakote
Upgrade your AR platform with the Moriarti AR-15 300 Blackout 10.5" Complete Upper Assembly, enginee..
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Moriarti AR-15 300 BLK 7.5" Honeycomb Chrome Moly Upper Assembly | Choose Color MLOK | Trident Cone Flash Can
Key Features: Premium Handguard: The 9" MLOK slim profile forearm is built for precision performa..
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AR-15 .300 AAC Blackout 7.5" Upper Assembly – 7" Moriarti M-LOK, Muzzle Shroud
The Moriarti AR-15 .300 AAC Blackout upper assembly features a 7.5-inch, 4150 CMV barrel with a nitr..
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AR-15 .300 Blackout 7.5" Upper Assembly – 7" M-LOK, Blue Shroud & Accents
The Moriarti AR-15 .300 AAC Blackout upper assembly features a 7.5-inch nitride-treated barrel with ..
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AR-15 300 Blackout 7.5" Pistol Zombie Slayer Upper Assembly / Mlok
Unleash superior performance with the AR-15 300 Blackout 7.5" Pistol Zombie Slayer Upper Assembly by..
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AR-15 300 Blackout 7.5" Patriotic Upper Assembly / Red Accents / Charging Handle / Shroud
The Moriarti AR-15 .300 AAC Blackout Patriotic Upper Assembly features a 7.5-inch 4150 chrome-moly s..