Aero Precision AR-15 M4E1 Builder Set with Lower Receiver, Upper Receiver, & Handguard - Custom Finish

The much-anticipated Aero Precision M4E1 Builder Sets are here! These unique finishes are available one time only and in limited quantities, so get one while you can!

Upper Receiver: 

The M4E1 Threaded Upper Receiver features a new angular machined design that helps it stand apart from standard mil-spec upper receivers. It is forged from 7075-T6 Aluminum, precision machined to work with all mil-spec AR15 parts and includes the port door and forward assist pre-installed.

The M4E1 Threaded Upper Receiver is designed to pair perfectly with Aero Precision's new M4E1 Lower Receiver, giving you a billet looking receiver set at a fraction of the billet price.

Features:

• New enhanced forging that gives the upper receiver a "billet look"
• New picatinny profile that blends seamlessly with Aero Precision's Enhanced and ATLAS Series Handguards
• M4 Feedramps
• .250 takedown pin holes
• Laser engraved T-marks
• Includes threaded forward assist roll pin
• Includes port door and forward assist

Includes:

• M4E1 Threaded Upper Receiver in Anodized Black
• Port Door and Forward Assist installed

Lower Receiver: 

The M4E1 Lower Receiver delivers billet aesthetics in a forged package. This custom designed enhanced forging is machined from 7075-T6 Aluminum and compatible with all mil-spec AR15 parts. Aside from the visual upgrades this custom engineered design provides that challenge much more expensive billet options, Aero Precision has added several functional features to the lower receiver to simplify the assembly process for the at home builder.

M4E1 Lower Receiver Improvements:

• Threaded Bolt Catch Roll Pin - Allows for simple installation of the bolt catch and virtually eliminates the chance to damage the finish during installation (pin included). 1/16" Hex Key required for assembly.
• Integrated Trigger Guard - Eliminates the possibility of breaking the trigger guard tabs by integrating the trigger guard into the lower, creating a stronger more rigid platform to build upon.
• Upper Tension Screw - Allows users to fine tune the fit of the upper and lower receiver using a nylon tipped tensioning set screw inserted in the grip tang of the lower receiver. This provides a tight fit with any standard AR15 upper receiver.
• Threaded Takedown Pin Detent Recess - Allows user to easily install the Takedown Pin detent and spring with the use of a 4-40 set screw (no more launching detents across the room).
• Increased Magwell Flare - Increased the flare of the magwell to aid in quick and efficient magazine changes.
• Marked and milled to accept short-throw safety selectors, but will work with standard selectors as well.

Includes:

• Stripped M4E1 Lower Receiver
• Nylon tipped tensioning set screw
• Threaded Bolt Catch Pin

Free Float Handguard: 

Each Builder Set will ship with your choice of Aero Precision handguard. See our custom options above to choose a handguard that will best suit your next build.