Receiver PartsAero PrecisionSold by Brownells

Aero Precision

M4e1-T 300 Blackout Complete Uppers - M4e1 300blk Assembled Upper 16''''bbl Threaded W/Rm15'''' Hg Fde

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

Complete Upper

From Aero Precision in 300

Includes Aero

Precision’s new ATLAS R-ONE Handguard

Atlas Attachment

System provides a durable, dependable

Handguard Is

Size and weight in mind

Slim Profile

Leaves plenty of real estate

$534.99
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SKU: 430103923

Overview

Built for a .300 Blackout setup, this complete upper is aimed at hunters and shooters who want a ready-to-use foundation with a streamlined handguard layout. The included ATLAS R-ONE handguard is designed to keep the profile slim while still leaving room for accessories, making it a practical choice for a field rifle or a compact hunting build. Aero Precision’s ATLAS attachment system provides a secure mounting platform without adding unnecessary bulk. It suits users who value a clean, adaptable upper and prefer to configure their rifle around specific hunting or range needs.

Why Hunters Choose the Aero Precision

Includes Aero

Precision’s ATLAS R-ONE handguard for

Handguard Is

Size and weight in mind

Plenty Real

Estate for attachment needs

Atlas Attachment

System offers a durable, dependable

Maintains Slim

Profile while preserving strength and

Key Features

  • Complete upper from Aero Precision in 300 Blackout configuration.
  • Includes Aero Precision’s new ATLAS R-ONE Handguard.
  • ATLAS attachment system provides a durable, dependable mounting platform.
  • Handguard is designed with size and weight in mind.
  • Slim profile leaves plenty of real estate for attachments.

Best Used For

  • Hunters wanting a complete upper with a slim handguard for streamlined setup
  • Users planning accessory-heavy builds needing ample mounting space on the handguard
  • Shooters who prefer Aero Precision components and the ATLAS attachment system
  • Field users looking for a compact-profile upper that keeps the front end uncluttered

Specifications

Assembly StatusAssembled
Attachment SystemATLAS
Barrel Length16 in
Barrel ThreadedYes
Caliber300 Blackout
HandguardATLAS R-ONE
Handguard ColorFDE
Handguard Design FocusSize and weight in mind
Handguard Length15 in
Handguard ProfileSlim
Handguard Real EstatePlenty of real-estate for attachment needs
Included ComponentsComplete upper with ATLAS R-ONE handguard
Mounting PlatformDurable and dependable
Product TypeComplete Upper
Strength And StabilityMaintains strength and stability
Upper ModelM4E1

Pros

  • Includes Aero Precision’s ATLAS R-ONE handguard for a slim, streamlined setup.
  • Handguard is designed with size and weight in mind.
  • Provides plenty of real estate for attachment needs.
  • ATLAS attachment system offers a durable, dependable mounting platform.
  • Maintains a slim profile while preserving strength and stability.

Considerations & Trade-offs

  • The ATLAS R-ONE handguard is designed with a slim profile and size/weight in mind, so accessory mounting space is available without adding bulk, but it is still a more streamlined setup than a fuller-profile handguard.
  • This is a complete upper, so it is intended for pairing with a compatible lower; buyers should confirm the rest of the rifle configuration fits their intended use before purchase.
  • The product is chambered in 300 Blackout, which makes caliber selection straightforward, but it also means this upper is purpose-built around that cartridge rather than a general-purpose option.
  • The description emphasizes the handguard and upper assembly, but it does not provide detailed component specifications here, so shoppers who need exact part-level details should verify the full spec sheet before ordering.

Suggested Comparisons

  • AR-15 complete upper receivers
  • 300 Blackout upper assemblies
  • Free-float handguard upper builds
  • Aero Precision upper components

Suggested Accessories

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

Frequently Asked Questions

What is included with this upper receiver assembly?

The source data says this is a complete upper from Aero Precision and that it includes the new ATLAS R-ONE Handguard. No other included components are listed.

What handguard system does this upper use?

It uses Aero Precision’s ATLAS R-ONE Handguard with the proprietary ATLAS attachment system.

What does the product data say about the handguard’s design?

The handguard is described as being designed with size and weight in mind, while still providing plenty of real estate for attachment needs. It is also described as maintaining a slim profile.

Is this upper chambered in 300 Blackout?

Yes. The product title identifies it as a 300 Blackout complete upper.

What finish or color is indicated in the product title?

The title includes "Fde," which indicates a Flat Dark Earth color reference. The source data does not provide additional finish details.