Aero Precision M4E1-E Complete Upper, 10" 300 Blackout Pistol Barrel, 9.3" Enhanced MLOK HG - FDE Cerakote

Fully Assembled and Warrantied by Aero Precision
SKU: APAR640222M4

Original price was: $655.00.Current price is: $466.88.

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Aero Precision M4E1-E Complete Upper, 10″ 300 Blackout Pistol Barrel, 9.3″ Enhanced MLOK HG – FDE Cerakote

The Aero Precision Complete Upper Receiver epitomizes speed, efficiency, and dependability for fashioning a semi-custom AR15 rifle. Crafted with meticulous precision, this 300 Blackout M4E1 Threaded Complete Upper boasts a 10″ Pistol barrel and a 9.3″ Gen 2 Enhanced handguard. Meticulously machined, comprehensively assembled, and subject to rigorous test-firing by skilled Aero Precision armorers, it guarantees unparalleled performance.

* NFA Rules apply for this item.
* The muzzle device is NOT pinned nor welded to the barrel.
* Does not include Bolt Carrier Group or Charging Handle.


  • M4E1 Threaded Assembled Upper Receiver – Magpul FDE Cerakote
  • 9.3″ M-LOK Gen 2 Enhanced Handguard – Magpul FDE Cerakote
  • 10″ 300 BLK Pistol Barrel
  • Low-profile Gas Block and Gas Tube
  • Standard A2 Flash Hider

M4E1 Threaded Upper Receiver Features:

  • New enhanced forging gives the upper receiver a “billet look.”
  • M4 Feed ramps
  • .250 takedown pin holes
  • Includes port door and forward assist installed

Gen 2 Enhanced Handguard Features:

  • 1pc free-float design
  • Built-in anti-rotation tabs
  • Scalloped rails
  • Quick disconnect sling socket at the 3, 6, and 9 o’clock positions
  • Compatible with low-profile gas blocks
  • 1.78″ Inside diameter, fits most 1.5″ suppressors
  • Additional milling along flats to aid with gripping and visual appeal
  • New profile for the continuous Picatinny top rail

300 BLK Barrel Features:

  • .300 BLK 1/7 twist, 4150 CrMoV, QPQ finish
  • .750 gas block journal
  • Pistol gas system
  • M4 Feed Ramp Extension
  • HP and MPI tested

Product Information


Aero Precision








9.3" M-LOK


300 Blackout



Gas System


Twist Rate


Barrel Finish

QPQ Nitride

Muzzle Thread



Enhanced, M4E1


4150 Chrome Moly Vanadium, 6061-T6 Aluminum


Standard AR15 components

Made in USA


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Arm or Ally is a stocking dealer for all Aero Precision, Faxon Firearms, Ballistic Advantage, HOLOSUN, Toolcraft, Elftmann Tactical, Timney, TriggerTech, HIPERFIRE and was named the #1 Overall E-Commerce Dealer for Aero Precision Products in 2020!

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