Aero Precision 5.56 NATO M4E1 ATLAS R-ONE Completed Upper

Barrel lengths available in 10.5″ or 16″
Aero Precision 5.56 NATO M4E1 ATLAS R-ONE Completed Upper is the most efficient way to assemble your own custom firearm; fully assembled and warrantied by Aero Precision.  The R-ONE handguards are designed with size and weight in mind, while still providing plenty of real-estate to accommodate any attachment needs the end user may have. Aero Precision’s proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.
*NFA Rules apply for the 10.5″ barreled model.
**The muzzle devices are NOT pinned nor welded to the barrel.
***Does not include Bolt Carrier Group or Charging Handle.

M4E1 Threaded Upper Receiver Features:
- New enhanced forging that gives the upper receiver a “billet look”
- M4 Feedramps
- .250 takedown pin holes
- Laser engraved T-marks
- Includes port door and forward assist installed
ATLAS R-ONE Handguard Features:
- Full top picatinny rail for optional attachments
- 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 Mid-Length Barrel Features:
- 5.56 NATO 10.5″ Carbine or 16″ Mid-length, 1/7 twist, 4150 CrMoV, QPQ, gas port drilled
- .750 gas block journal
- Mid-length gas system, .0785 gas port
- M4 Feed Ramp Extension
- HP and MPI tested
- Standard A2 flash hider
Also available in other configurations
….with ATLAS S-ONE Handguards
….with Enhanced Handguards
- M4E1 Threaded Assembled Upper Receiver
- ATLAS R-ONE Handguard
- 10.5″ or 16″ 5.56 CMV Barrel
- Low Profile Gas Block and Gas Tube
Product Information
Manufacturer:  Aero Precision
Assembled: Yes
Finish: Anodize
Color: Black
Caliber: 5.56 NATO
Platform: AR15
Complete Upper Series: ATLAS
Handguard OD:  1.5″
Handguard ID: 1.3″
Handguard Type: M-LOK
Gas Block Diameter: .750
Muzzle Device: A2 Flash Hider
Muzzle Threads: 1/2×28 TPI
Barrel Length: 10.5″ | 16″
Barrel Finish: QPQ Melonite
MSRP: Varied by model
Arm or Ally is a stocking dealer for all Faxon Firearms, Ballistic Advantage, Rosco Manufacturing, Aero Precision, Toolcraft, Elftmann Tactical, HIPERFIRE and more. See our growing inventory of AR Parts and Reloading Components.
MPN#: APAR700702M2

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