AERO M4E1-T COMPLETE UPPER 16 350 QPQ CARB

The Aero M4E1-T complete upper in .350 Legend is a ready-to-go upper receiver assembly built for shooters who want a modern, purpose-built platform without the assembly hassle. This 16-inch carbine features Aero's M4E1 threaded upper receiver paired with a 15-inch ATLAS R-ONE handguard and a CMV barrel designed for reliable, accurate shooting. Whether you're building a lightweight hunting rifle, a versatile home-defense carbine, or a precision intermediate-caliber platform, this complete upper gives you a solid foundation that's already assembled and tested.

The M4E1-T upper receiver sets itself apart with its billet-inspired forging and enhanced picatinny profile that integrates seamlessly with modern handguards. Standard M4 feedramps, .250 takedown pin holes, and laser-engraved T-marks give you a refined, professional finish. Port door and forward assist come installed. The ATLAS R-ONE handguard brings a slim, purpose-driven design: full top picatinny rail for optics and accessories, QD sling attachment points at 3, 6, and 9 o'clock, and low-profile gas block compatibility. Its proprietary ATLAS mounting system delivers the durability and stability Aero shooters expect without unnecessary bulk.

The 16-inch .350 Legend barrel is where precision meets reliability. DMR profile, 4150 CrMoV construction with QPQ finishing, and carbine-length gas system keep recoil manageable while supporting accurate fire. The barrel is HP and MPI tested, gas port drilled at .0785 inches, and topped with a standard A2 flash hider. M4 feed ramp extension ensures reliable feeding. This is a complete upper assembly—bolt carrier group and charging handle are not included, so you'll supply those separately to finish the build.

Key Features

• M4E1-T threaded upper receiver with billet-inspired forging and enhanced picatinny profile
• 15-inch ATLAS R-ONE handguard with full top rail and QD sling mounts at 3, 6, and 9 o'clock
• 16-inch .350 Legend CMV barrel, DMR profile, QPQ finish, carbine-length gas system
• Low-profile gas block and carbine-length gas tube included
• M4 feedramps and standard A2 flash hider
• HP and MPI tested barrel for consistent reliability
• Factory assembled and tested—no upper receiver gunsmithing required

Specifications

Frequently Asked Questions

Is this a complete upper or do I need additional parts?

This is a complete, factory-assembled upper receiver assembly. You will need to supply a bolt carrier group (BCG) and charging handle separately to complete a functional rifle or SBR build.

What is the ATLAS R-ONE handguard compatible with?

The ATLAS R-ONE handguard is designed for mil-spec AR15 upper receivers and barrels. It features low-profile gas block compatibility and works with Aero's proprietary ATLAS mounting system.

What is .350 Legend ammo good for?

We can confirm this upper is chambered in .350 Legend and is built to Aero's specifications. Ammunition suitability and performance depend on your intended use and should be verified with ballistics and hunting resource guides appropriate to your application.

Can I use this upper with my existing lower receiver?

This upper receiver is designed to work with standard AR15-pattern lower receivers. Verify compatibility with your specific lower before assembly.