Aero Precision M4E1-T Complete Upper, 16" 5.56 Mid-Length Barrel, 15" ATLAS R-ONE MLOK HG, Adj. Gas Block, VG6 Epsilon 556, BREACH Charging Handle, BCG - Anodized Black

SKU: APSL100388
Fully Assembled and Warrantied by Aero Precision

In stock

Ballistic Advantage Authorized DealerAero Precision Authorized Dealer

Aero Precision M4E1-T Complete Upper, 16″ 5.56 Mid-Length Barrel, 15″ ATLAS R-ONE MLOK HG, Adj. Gas Block, VG6 Epsilon 556, BREACH Charging Handle, BCG – Anodized Black

The Aero Precision Complete Upper Receiver epitomizes speed, efficiency, and dependability for fashioning a semi-custom AR15 rifle. Crafted with meticulous precision, this 5.56 NATO M4E1 Threaded Complete Upper boasts a 16″ Mid-Length barrel, 15″ ATLAS R-ONE handguard, BREACH Charging Handle and Phosphate 5.56 NATO BCG w/ C158 Bolt. Meticulously machined, comprehensively assembled, and subject to rigorous test-firing by skilled Aero Precision armorers, it guarantees unparalleled performance.

* Includes Bolt Carrier Group, BREACH Charging Handle, Adjustable Gas Block, and VG6 Muzzle Device.


  • M4E1 Threaded Assembled Upper Receiver – Anodized Black
  • 15″ ATLAS R-ONE Handguard – Anodized Black
  • 16″ 5.56 CMV Barrel, Mid-Length
  • .750 Adjustable Gas Block and Mid-Length SS Gas Tube
  • AR15 BREACH Ambidextrous Charging Handle (Large Lever)
  • AR15 5.56 Phosphate C158 Bolt Carrier Group
  • VG6 Epsilon 556 Muzzle Device

M4E1 Threaded Upper Receiver Features:

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

ATLAS R-ONE Handguard Features:

Aero Precision’s ATLAS attachment system is a secure and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.

  • Continuous top Picatinny rail
  • Quick disconnect sling socket at the 3, 6, and 9 o’clock positions
  • Compatible with low-profile gas blocks
  • 1.3″ Inside diameter
  • 1.5″ Outside diameter

5.56 NATO Barrel Features:

  • 16″5.56 NATO 1/7 twist, 4150 CrMoV, QPQ finish
  • .750 gas block journal
  • Mid-Length gas system
  • M4 Feed Ramp Extension
  • HP and MPI tested

Product Information


Aero Precision

Made in USA





5.56 NATO

Attachment Type


Coating Type

Anodized Black



Barrel Length


Gas System


Barrel Finish

QPQ Nitride

Muzzle Thread



4150 Chrome Moly Vanadium, 6061-T6 Aluminum


Standard AR15 components

Part Type

Upper Receiver Parts

Gas Block Diameter




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