Aero Precision M4E1-T 7.3" ATLAS R-ONE Builder's Set - FDE Cerakote

SKU: APCS700112

Original price was: $575.00.Current price is: $419.57.

In Stock

In stock



Aero Precision M4E1-T 7.3″ ATLAS R-ONE Builder’s Set – FDE Cerakote

The Aero Precision M4E1 ATLAS Builder’s Sets offered by Arm or Ally are a perfect way to get your M4E1 build headed in the right direction using key components purposely engineered to fit and function together as one solid unit.  

Builder’s Sets Include

  • M4E1 Threaded Assembled Upper Receiver – FDE Cerakote
  • M4E1 Stripped Lower Receiver – FDE Cerakote
  • 7.3″ ATLAS R-ONE M-LOK Handguards, FDE Cerakote

*Note: Barrel Nut & Mounting Kit included.

M4E1-T Upper Receiver Features:

  • New enhanced forging gives the upper receiver a “billet look.”
  • New Picatinny profile blends seamlessly with Enhanced and ATLAS Series Handguards
  • M4 Feedramps
  • .250 takedown pin holes

M4E1 Lower Receiver Features:

  • Threaded Bolt Catch Roll Pin – Allows for simple bolt catch installation and virtually eliminates the chance of damaging the finish during installation (pin included).
  • 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 – This 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 users to install the Takedown Pin detent easily and spring using a 4-40 set screw (no more launching detents across the room).
  • Increased Magwell Flare – Increased the magwell flare to aid in quick and efficient magazine changes.

ATLAS R-ONE Handguard

The new Aero Taper Lock Attachment System (ATLAS) is functional and aesthetically pleasing. It features two mirrored tapered locking nuts that provide evenly distributed clamping pressure across a custom-engineered barrel nut using a turnbuckle screw. A ratcheting detent further secures the design while providing positive registration during installation. By design, the even pressure of the ATLAS system avoids distortion of the handguard often seen with current applications during installation.

Handguard Features:

  • Continuous top Picatinny rail
  • Quick disconnect sling socket at the 3, 6, and 9 o’clock positions
  • Compatible with low-profile gas blocks
  • 1.5″ Inside diameter
  • Compatible with mil-spec AR15 upper receivers and barrels

Product Information


Aero Precision










6061-T6 Aluminum, 7075-T6 Aluminum




Standard AR15 components

Made in USA



7.3" M-LOK


Hardware Mounting Weight – 1.9oz


Before MAKING your purchase, please carefully review the information below.

Click Here for FFL Order Processing Lead Times

Review our FFL Ordering Instructions HERE before placing your order.

  • Prices do not include your dealer’s transfer fees.
  • Not eligible for return after transferred into your possession via ATF Form 4473.
  • There will be a 30% restocking fee on all controlled items returned because of failed background checks.

Federal law requires that you be 21 years of age or older to purchase a pistol, stripped receiver, or frame. If a frame or receiver can only be made into a long gun (rifle or shotgun), it is still a frame or receiver, not a handgun or long gun. However, they are still “firearms” by definition and are subject to the same GCA limitations as any other firearm. See Section 921(a)(3)(b). 18 U.S.C. Section 922(b)(1) makes it unlawful for a licensee to sell any firearm other than a shotgun or rifle to any person under the age of 21.

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Arm or Ally

Arm or Ally is a stocking dealer for all Aero Precision, Faxon Firearms, Ballistic Advantage, HOLOSUN, Toolcraft, Elftmann Tactical, Timney, TriggerTech, HIPERFIRE and was named the #1 Overall E-Commerce Dealer for Aero Precision Products in 2020!

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