Epc-9 9Mm Assembled Upper Threaded 11'' Bbl 10.3'' Handguard

The Aero Precision EPC-9 9mm assembled upper receiver with threaded 11" barrel and 10.3" handguard is a complete, ready-to-run upper assembly built for 9mm AR-platform pistols and short-barreled rifles. This is a fully assembled unit—no additional fitting required—making it an excellent choice for builders who want a proven upper without the guesswork, or shooters looking to swap uppers on an existing lower. The EPC-9 receiver is purpose-built for 9mm, incorporating last-round bolt hold-open functionality and Aero's reputation for precision machining and durability.

The included ATLAS R-ONE handguard strikes a balance between weight savings and mounting real estate. Its slim 1.3" inside diameter keeps the overall package nimble, while the integrated picatinny rail on top and quick-disconnect sling sockets at 3, 6, and 9 o'clock positions give you flexible attachment options without unnecessary bulk. The proprietary ATLAS mounting system is rock-solid—Aero's handguard platform has earned trust across countless builds for stability and reliability.

Underneath, you're getting a 9x19 chrome moly vanadium barrel with a QPQ corrosion-resistant finish and a 1-in-10 twist, threaded for standard 1/2"x28 muzzle devices. The muzzle device arrives unpin­ned and unwelded, giving you the option to permanently attach a suppressor or muzzle brake if you choose. The EPC-9 upper accepts standard AR15-compatible barrel nuts and handguards, so future upgrades remain straightforward. Note: This upper does not include a bolt carrier group or charging handle—those are sourced separately to match your preferred specs and shooting style.

Whether you're building a duty-ready 9mm PCC, a compact home-defense rifle, or just consolidating your AR platform around a trusted caliber, the Aero Precision EPC-9 gives you the engineering and fit quality you expect from the brand, assembled and tested and ready to mount to your lower.

Key Features

• Last-round bolt hold-open mechanism for 9mm operation
• Fully assembled and ready to install on a compatible lower receiver
• Forged 7075-T6 aluminum EPC-9 upper receiver, machined with precision and dimpled for handguard timing
• ATLAS R-ONE handguard with integrated full-length picatinny rail and QD sling sockets (3, 6, 9 o'clock)
• 9x19 chrome moly vanadium barrel with QPQ finish inside and out
• Threaded 1/2"x28 for easy muzzle device installation (unpin­ned)
• Accepts standard AR15 barrel nuts and handguards for future upgrades

Specifications

Frequently Asked Questions

What lower receiver does this upper fit?

This is an EPC-9 upper receiver with standard AR15 takedown and pivot pin lug pattern. It will mate with any mil-spec AR15 lower receiver. If your lower is chambered for a different caliber, you'll need to ensure it's compatible with 9mm or plan to build a dedicated 9mm lower.

What's included, and what do I need to source separately?

The upper arrives fully assembled and ready to install: you get the EPC-9 receiver, ATLAS R-ONE handguard, 11" 9mm barrel, and muzzle device. You will need to source a bolt carrier group (BCG) and charging handle separately to complete the assembly.

Can I use a different handguard?

Yes. The EPC-9 upper is designed to accept standard AR15-compatible barrel nuts and handguards, so you can swap the included ATLAS R-ONE for another mil-spec handguard if you prefer a different profile or feature set.

Is the muzzle device permanent?

No. The muzzle device comes unpinned and unwelded, so you can remove it or replace it with a suppressor or other muzzle device of your choice. If you want to permanently attach a suppressor, you can have the muzzle device pinned and welded by a gunsmith.