Aero Precision M4E1 Threaded 6.5 Grendel Assembled Upper Receiver W/Atlas R-One 20" Barrel

Aero Precision M4E1 Threaded 6.5 Grendel Assembled Upper Receiver W/Atlas R-One 20" Barrel

Upgrade the performance of your AR15 build with this 6.5 Grendel Complete Upper Receiver. Designed to be a low recoil/high accuracy cartridge, the 6.5 Grendel is ideal for those looking to stretch the legs of their AR15 rifle, with proven results at 1000+ yards.



This complete upper includes Aero Precisions new ATLAS R-ONE Handguard! 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 Precisions 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.



Includes :

M4E1 Threaded Assembled Upper Receiver

ATLAS R-ONE Handguard of choice

6.5 Grendel 18" Stainless Steel, Rifle Length Barrel

.750 Low Profile Gas Block and Rifle Length Gas Tube

A2-style Flash Hider

Product comes assembled

The 6.5 Grendel is designed on the AR15 platform. You will need to purchase a 6.5 Grendel specific bolt and magazine. All other components are standard to the AR15 platform. This upper assembly 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 our Enhanced Series Handguards

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

Compatible with mil-spec AR15 upper receivers and barrels



6.5 Grendel 20" Stainless Steel, Rifle Length Barrel Features :

6.5 Grendel 20" Rifle Length Barrel

416R Stainless Steel finish

1/8 twist

5/8x24 Threaded Pitch

DMR Profile

.750 gas block journal

Rifle length gas system

M4 Feed Ramp Extension

HP and MPI tested

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