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Aero Precision M4E1 6.5 Grendel Partial Upper Receiver w/ Atlas R-One Handguard - 20" Black

AR-15 Partial Upper Receiver

$614.99

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 Precision's 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. 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.


Includes:

  • M4E1 Threaded Assembled Upper Receiver
  • ATLAS R-ONE Handguard of choice
  • 6.5 Grendel 20" 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
More Information
SKU APAR700725M53
Product Type AR-15 Partial Upper Receiver
Manufacturer Aero Precision
Gas Block Diameter .750"
Thread Pitch 5/8x24
Inside Diameter 1.3"
Gas Length Rifle
Barrel Length 20"
Caliber 6.5 Grendel

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