Aero Precision M4E1 Threaded Barreled AR-15 Upper 5.56 Rifle Atlas R-One - 18"

Aero Precision M4E1 Threaded Barreled AR-15 photo
Availability: Within 5 days
SKU: APAR700705M8
Barcode: 8600054154760
Color: Black
Caliber: 5.56 mm
Length: 18"
Compatibility: AR-15
Thread 1: 1/2"-28
Material: 41V50 Chrome Moly Vanadium Steel
Coating: Salt Bath Nitride
Cookies are disabled in your browser. The website functionality may be broken.

The Aero Precision AR-15 barreled upper receiver is built around the M4E1 Threaded upper receiver designed for use with standard barrel nut setups. The receiver is forged from 7075-T6 aluminum and precision machined to M4E1 specs to ensure proper fit with Mil-Spec and aftermarket parts. It is matte black hardcoat anodized and features laser engraved T-marks. This 18” 5.56 barreled upper comes with the Atlas R-One M-LOK free float handguard with a full length picatinny top rail and a slim 1.3" inner diameter.


  • 18” 5.56 NATO
  • 4150 Chrome Moly Vanadium barrel
  • HPT and MPI
  • Black Nitride finish
  • 1:7 twist rate
  • Rifle length gas system
  • M4E1 Threaded forged 7075-T6 upper
  • Hardcoat anodized
  • Laser engraved T-marks
  • Scalloped picatinny top rail
  • Built in anti-rotation tabs
  • M-LOK slots
  • Does not include BCG or charging handle


The 5.56 NATO 18” barrel is machined from 4150 CMV steel with a salt bath Nitride finish, a rifle length gas system, and a 1:7 twist rate. It has an M4 feed ramp barrel extension and is magnetic particle inspected as well as high pressure tested. A standard A2 flash hider with 1/2x28 threading is attached to the muzzle.

Aero Precision takes some of the most state-of-the-art manufacturing techniques and equipment derived from their work in the aerospace industry and applies it to their products in the firearms industry. They have utilized their knowledge from years of building aircraft components to design and engineer AR-15 handguards, receiver sets, scope mounts, and more. They treat every product as if it were a precision flying machine and adhere to strict quality standards to ensure law enforcement, military, and civilian customers receive a product they can rely on.

Leave a comment

Cookies are disabled in your browser. The website is working in a limited mode. To use full website functionality you should enable cookies in your browser.