Inter-Store Transfer

If this item is out of stock at your local RifleGear but available at our other location, no problem. Just place your order and select In-Store Pickup as the shipping method. As long as the item is legal in your location, we will transfer the item for you. You will be notified by email once your item has arrived at the destination.
The Aero Precision M4E1 complete upper receiver includes an M4E1 Threaded upper receiver, ATLAS R-ONE handguard, 14.5″ 5.56 Mid-Length barrel, low profile gas block and VG6 Gamma 556 SL muzzle device(pin/welded).
*This upper receiver group DOES NOT include a BCG or charging handle

M4E1 Threaded Upper Receiver Features:

New enhanced forging that gives the upper receiver a “billet look”

New picatinny profile that blends seamlessly with Aero Precision Enhanced Series Handguards

M4 Feedramps

.250 takedown pin holes

Laser engraved T-marks

Includes port door and forward assist installed

ATLAS S-ONE Handguard Features:

Full top 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

Compatible with mil-spec AR15 upper receivers and barrels

14.5″ 5.56 Mid-Length Barrel Features:

Chamber: 5.56

Length: 14.5″

Twist: 1 in 7

Threading: 1/2″x28

Material: Chrome Moly Vanadium

Finish: QPQ corrosion resistant finish both inside and out

Gas Block: .750

Gas Port: .0785

Gas System Length: Mid

Weight: 26oz

M4 Barrel Extension

HP and MPI Tested