M4E1 Assembled Upper Black AR15 APAR700201AC

The Aero Precision M4E1 Assembled Upper Receiver is a forged AR15 upper built for shooters who want precision engineering without the billet price tag. Machined from 7075-T6 aluminum and threaded to accept standard AR15 barrel nuts, this upper delivers a refined, angular profile that stands out visually while maintaining full compatibility with mil-spec AR15 parts. It arrives assembled with the port door and forward assist already installed, so you can focus on building instead of wrestling with tiny springs.

The M4E1's enhanced forging gives it a billet-like appearance that pairs beautifully with Aero Precision's Enhanced and ATLAS Series handguards, thanks to a picatinny profile designed for seamless integration. The receiver features M4 feedramps and .250 takedown pin holes, ensuring reliable feeding and a solid lockup with mil-spec lower receivers—including Aero's own M4E1 lower for a cohesive, purpose-built upper and lower set.

Whether you're building a duty rifle, a precision range gun, or a hunting platform, this upper receiver handles the job with the attention to detail Aero Precision is known for. It's a smart choice for anyone who wants quality engineering and thoughtful design without compromise.

Key Features

• 7075-T6 forged aluminum construction with enhanced angular design
• Threaded to accept standard AR15 barrel nuts
• Port door and forward assist pre-installed
• M4 feedramps for reliable feeding
• .250 takedown pin holes for mil-spec compatibility
• Picatinny profile compatible with Aero's Enhanced and ATLAS handguards
• Billet-like aesthetics at a fraction of billet receiver cost

Specifications

Frequently Asked Questions

Is the M4E1 upper compatible with mil-spec AR15 lower receivers?

Yes. The M4E1 upper is precision machined to work with all mil-spec AR15 parts and lower receivers, including Aero Precision's M4E1 lower for a matched set.

What barrel nut does this upper use?

The M4E1 is threaded to accept a standard AR15 barrel nut, which is widely available and works with most common AR15 barrels.

What comes installed on this upper receiver?

The port door and forward assist are pre-installed, along with the threaded forward assist roll pin. You don't need to assemble those components yourself.

Which handguards are compatible with the M4E1 upper?

The M4E1's picatinny profile is designed to blend seamlessly with Aero Precision's Enhanced and ATLAS Series handguards, though it will work with any picatinny-compatible handguard.