Receiver PartsAero PrecisionSold by Brownells

Aero Precision

M4e1-T 300 Blackout Complete Uppers - M4e1 300blk Assembled Upper 8''''bbl Threaded W/Rm7.3'''' Hg Fde

Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.

Complete Upper

From Aero Precision for 300

Includes New

ATLAS R-ONE Handguard

Handguard Is

Size and weight in mind

Plenty Real

Estate for attachment needs

Uses Aero

Precision's proprietary ATLAS attachment system

$569.99
View on Brownells

You'll be taken to Brownells to complete your purchase.

Hunter's Outpost earns a commission from affiliate links at no extra cost to you.

SKU: 430103925

Overview

Built for a compact 300 Blackout setup, this complete upper pairs an assembled upper with an 8-inch threaded barrel and Aero Precision’s ATLAS R-ONE handguard. The slim handguard design is intended to keep the front end streamlined while still leaving room for accessories and other setup needs. It is a practical option for hunters and shooters who want a shorter upper with a clean, adaptable layout. The FDE finish gives it a distinctive look without changing the straightforward purpose of the platform.

Why Hunters Choose the Aero Precision

Includes Aero

Precision’s new ATLAS R-ONE Handguard

Slim-profile Handguard

Size and weight in mind

Ample Real

Estate for mounting user-selected accessories

Atlas Attachment

System is described as durable

Complete Upper

Arrives assembled for straightforward integration

Key Features

  • Complete upper from Aero Precision for 300 Blackout builds.
  • Includes the new ATLAS R-ONE Handguard.
  • Handguard is designed with size and weight in mind.
  • Provides plenty of real estate for attachment needs.
  • Uses Aero Precision's proprietary ATLAS attachment system.
  • ATLAS system is described as durable, dependable, and slim-profiled.

Best Used For

  • Hunters wanting a compact 300 Blackout complete upper for a streamlined setup
  • Users planning to mount accessories on a slim handguard with ample attachment space
  • Those who prefer Aero Precision’s ATLAS R-ONE handguard and mounting system
  • Shooters building a short-barreled upper for a compact rifle configuration

Specifications

AssembledYes
Attachment SystemATLAS attachment system
Barrel Length8"
Barrel ThreadedYes
Caliber300 Blackout
HandguardATLAS R-ONE Handguard
Handguard ColorFDE
Handguard Length7.3"
Upper TypeComplete upper

Pros

  • Includes Aero Precision’s new ATLAS R-ONE Handguard for a streamlined setup.
  • Slim-profile handguard is designed with size and weight in mind.
  • Provides ample real estate for mounting user-selected accessories.
  • ATLAS attachment system is described as durable and dependable.
  • Complete upper arrives assembled for straightforward integration.

Considerations & Trade-offs

  • The 7.3" handguard keeps the front end compact, so there is less room than on longer setups for lights, sling hardware, or other accessories.
  • The ATLAS R-ONE is designed with size and weight in mind, which can be a trade-off if you prefer a more substantial handguard feel.
  • This is a complete upper only, so it still requires a compatible lower and the rest of the rifle setup to be usable.
  • The short-barrel 300 Blackout format is purpose-built and compact, but it is more specialized than a general-purpose full-length configuration.

Suggested Comparisons

  • AR-15 complete upper receivers
  • 300 Blackout upper assemblies
  • Short-barreled rifle uppers
  • Free-float handguard upper builds

Suggested Accessories

  • Optic mount
  • Backup iron sights
  • Weapon light
  • Sling

Frequently Asked Questions

What is included with this complete upper?

The source data says this is a complete upper and that it includes Aero Precision’s ATLAS R-ONE Handguard. It also identifies the product as an assembled upper in 300 Blackout with an 8" barrel and threaded configuration. No other included components are specified.

Is this upper chambered in 300 Blackout?

Yes. The product title identifies it as a 300 Blackout complete upper and an assembled upper in 300blk.

What handguard does this upper use?

It uses Aero Precision’s ATLAS R-ONE Handguard. The description says the handguard is designed with size and weight in mind and offers plenty of real estate for attachments.

Does the handguard have a mounting system?

Yes. The description states that the handguard uses Aero Precision’s proprietary ATLAS attachment system, described as a durable and dependable mounting platform with a slim profile.

What finish or color is listed for this upper?

The product title includes FDE, which indicates the listed color/finish in the provided data. No further finish details are given.