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Aero Precision EPC-9 Threaded 9mm Partial Upper Receiver w/ Atlas S-One Handguard - 11"

AR-9 Partial Upper Receiver


This EPC-9 Complete Upper Receiver comes standard with Aero Precisions ATLAS S-ONE Handguard. The S-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.



  • EPC-9 Upper Receiver
  • 10.3" ATLAS S-ONE Handguard
  • 11" 9mm CMV Barrel
  • Product comes assembled
  • This complete upper receiver does not include BCG or Charging Handle.
  • The muzzle device included with this complete upper receiver is NOT pinned nor welded to this barrel.


EPC-9 Upper Receiver Features:

  • Last round bolt hold open mechanism
  • Accepts most AR15 compatible barrel nuts and handguards
  • Dimple above threads to allow for proper handguard timing
  • Standard AR15 takedown/pivot pin lug pattern
  • Machined from custom forged 7075-T6 aluminum


ATLAS S-ONE Handguard Features:

  • Full top picatinny rail for optional attachments
  • Quick disconnect sling socket at the 3, 6 and 9 o'clock positions
  • 1.3" Inside diameter
  • 1.5" Outside diameter
  • Compatible with mil-spec AR15 upper receivers and barrels


11" 9mm Barrel Features:

  • Chamber: 9x19
  • Length: 11"
  • Twist: 1 in 10
  • Threading: 1/2"x28
  • Material: Chrome Moly Vanadium
  • Finish: QPQ corrosion resistant finish both inside and out



  • Platform: EPC-9
  • Weight(s): 34.6 oz
More Information
SKU APAR620103M86
Product Type AR-9 Partial Upper Receiver
Manufacturer Aero Precision
Thread Pitch 1/2x28
Color Black
Rail Length 10.3"
Option AR-9
Barrel Length 11"
Caliber 9mm
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