Aero Precision M4E1 Upper Receiver Complete .300 Blackout 8" Barrel Black

Aero Precision M4E1 Upper Receiver Complete .300 Blackout 8" Barrel Black

This complete upper includes Aero Precision’s new ATLAS S-ONE Handguard! The S-ONE line of handguards are designed with size and weight in mind, providing the perfect addition to your lightweight build. Their 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.



M4E1 Threaded Assembled Upper Receiver

7"" M-LOK ATLAS S-ONE Handguard with 8" .300 Blackout CMV Barrel

Low Profile Gas Block and Pistol Length Gas Tube in all makeups.

This complete upper does not include BCG or Charging Handle.

The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel.

M4E1 Threaded Upper Receiver Features :

New enhanced forging that gives the upper receiver a ""billet look""

New picatinny profile that blends seamlessly with our 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 :

Front and rear picatinny rail

Eliminated center of top rail for weight reduction

Indexing grooves in 12:00 position for positive grip control

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

8"" .300 Blackout Barrel Features :

Length: 8""

Twist: 1 in 7

Muzzle: 5/8x24 Threaded

Material: 4150 Crome Moly Vanadium

Finish: QPQ corrosion resistant finish both inside and out

Gas Block: .750

Gas Port: .109

Gas System Length: Pistol

Weight: 18 oz

M4 Barrel Extension

HP and MPI Tested

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