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M4e1 Upper Receivers Complete .300 Blackout - M4e1 300blk Assm Upper Gov 8''''bbl Pistol-Length Threaded Blk
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$518.99
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SKU: 100054453
Overview
Built for a lightweight .300 Blackout setup, this complete upper is centered around Aero Precision’s M4E1 threaded assembled upper receiver and ATLAS S-ONE handguard. The slim handguard profile is intended to keep the build compact while still offering a stable mounting platform for accessories. It’s a practical choice for hunters and shooters planning a streamlined pistol-length upper in .300 Blackout, with configuration options listed in the product details.
Why Hunters Choose the Aero Precision
Complete Upper
Includes Aero Precision's new ATLAS
Atlas Attachment
System offers a durable, dependable
Slim-profile Handguard
Supports a lightweight build
M4e1 Threaded
Assembled upper receiver included
.300 Blackout
Configuration options are listed in
Key Features
- Complete upper receiver for .300 Blackout builds
- Includes Aero Precision ATLAS S-ONE handguard
- ATLAS S-ONE design emphasizes size and weight savings
- Proprietary ATLAS attachment system provides a slim mounting platform
- M4E1 threaded assembled upper receiver included
- Available with multiple handguard and barrel length configurations
Best Used For
- Hunters building a lightweight .300 Blackout upper with a slim-profile handguard
- Shooters wanting a complete upper receiver for a compact, threaded pistol-length setup
- Users prioritizing a durable mounting platform with M-LOK accessory compatibility
- Owners assembling an Aero Precision-based build around the M4E1 threaded upper receiver
Specifications
| Barrel | CMV Barrel |
|---|---|
| Barrel Length | 7 in |
| Blade Finish | Black |
| Caliber | .300 Blackout |
| Gas System | Pistol-length |
| Handguard | ATLAS S-ONE Handguard |
| Handguard Interface | M-LOK |
| Handguard Length | 7 in |
| Product Type | Complete upper receiver |
| Threaded | Yes |
| Upper Receiver | M4E1 Threaded Assembled Upper Receiver |
| Variant Options | 7 in handguard with 7 in barrel; 9 in handguard with 10 in barrel; 12 in handguard with unspecified barrel |
Pros
- Complete upper includes Aero Precision's new ATLAS S-ONE handguard.
- ATLAS attachment system offers a durable, dependable mounting platform.
- Slim-profile handguard supports a lightweight build.
- M4E1 threaded assembled upper receiver included.
- .300 Blackout configuration options are listed in the product details.
Considerations & Trade-offs
- The ATLAS S-ONE handguard is built around a slim, lightweight profile, so it favors a streamlined setup over a bulkier, more accessory-heavy front end.
- This is a complete upper receiver assembly, which is useful for a matched build but leaves less room for component-by-component customization at the outset.
- The product is offered with multiple handguard and barrel-length configurations, so the exact setup should be confirmed before purchase to ensure it fits the intended role.
- The .300 Blackout chambering is specific to this upper, so it is best suited to hunters and shooters already planning around that cartridge rather than a general-purpose caliber choice.
Suggested Comparisons
- AR-15 upper receiver assemblies
- .300 Blackout complete uppers
- Lightweight handguard-equipped upper builds
Suggested Accessories
- M-LOK rail accessories
- Weapon light
- Sling
- Optic mount
Frequently Asked Questions
What is included with this complete upper receiver assembly?
The description says this complete upper includes an M4E1 threaded assembled upper receiver and an ATLAS S-ONE handguard. The listed .300 Blackout configuration options include a 7-inch M-LOK ATLAS S-ONE handguard with a 7-inch CMV barrel, a 9-inch M-LOK ATLAS S-ONE handguard with a 10-inch CMV barrel, or a 12-inch M-LOK ATLAS S-ONE setup, though the last option is cut off in the provided text.
Is this upper chambered for .300 Blackout?
Yes. The product title and description identify it as a .300 Blackout complete upper.
What handguard system does this upper use?
It uses Aero Precision's ATLAS S-ONE handguard with an ATLAS attachment system. The description says the handguard is designed with size and weight in mind and maintains a slim profile.
Does the product data specify barrel length and other barrel details?
Some configuration options are listed in the description, including 7-inch and 10-inch .300 Blackout CMV barrel pairings with matching handguard lengths. The provided text does not fully show every option, and it does not provide additional barrel specifications beyond what is listed.
Can I confirm the exact dimensions or performance characteristics from this listing?
No. The provided data does not include complete dimensions for every configuration, and it does not state performance claims such as accuracy, recoil behavior, or field use results.