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M4e1 5.56 Assembled Upper Receiver W/M-Lok Atlas S-One Handguard - M4e1 5.56 Assm Uppr 16'''' Mid-Len 15'''' M-Lok Atlas S-One Hg Blk
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$498.99
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SKU: 100054450
Overview
Built for a lightweight rifle setup, this complete upper pairs Aero Precision’s M4E1 threaded assembled upper receiver with the ATLAS S-ONE handguard and a slim M-LOK mounting platform. It is configured around a 16" 5.56 mid-length barrel, making it suited to hunters and shooters who want a streamlined upper for general field use or range work. The ATLAS attachment system is designed to keep the profile compact while still providing a secure accessory interface. For buyers prioritizing a lighter, cleaner build, this upper offers a focused set of components without unnecessary bulk.
Why Hunters Choose the Aero Precision
Complete Upper
Includes Aero Precision's ATLAS S-ONE
Slim-profile Atlas
Attachment system is described as
Designed Size
Size and weight in mind
M4e1 Threaded
Assembled upper receiver included
Choice 12-inch
15-inch M-LOK ATLAS S-ONE handguard
Key Features
- Complete upper from Aero Precision with M4E1 threaded assembled upper receiver.
- Includes ATLAS S-ONE handguard designed with size and weight in mind.
- Proprietary ATLAS attachment system provides a durable, dependable mounting platform.
- Slim-profile handguard maintains strength and stability without added bulk.
- Available with 12-inch or 15-inch M-LOK ATLAS S-ONE handguard options.
- Configured with a 16-inch 5.56 Mid CMV barrel and low profile gas block.
Best Used For
- Hunters building a lightweight 5.56 upper for a streamlined rifle setup
- Users wanting a complete upper with M-LOK handguard and assembled receiver
- Shooters who prefer a slim-profile handguard for accessory mounting without added bulk
- Those configuring a mid-length 16-inch upper for general-purpose field use
- Aero Precision fans seeking a matched upper for a lightweight build
Specifications
| Atlas Attachment System | Proprietary ATLAS attachment system |
|---|---|
| Barrel Length | 16" |
| Barrel Profile | Mid CMV |
| Caliber | 5.56 |
| Gas Block | Low Profile Gas Block |
| Gas Tube Length | Mid-Length |
| Gas Tube Option | Rifle Length Gas Tube |
| Handguard | ATLAS S-ONE Handguard |
| Handguard Length | 15" |
| Handguard Mounting System | M-LOK ATLAS S-ONE |
| Rifle Barrel Option | 18" Rifle Barrel |
| Upper Receiver | M4E1 Threaded Assembled Upper Receiver |
Pros
- Complete upper includes Aero Precision's ATLAS S-ONE handguard.
- Slim-profile ATLAS attachment system is described as durable and dependable.
- Designed with size and weight in mind for lightweight builds.
- M4E1 threaded assembled upper receiver included.
- Choice of 12-inch or 15-inch M-LOK ATLAS S-ONE handguard options.
Considerations & Trade-offs
- The ATLAS S-ONE handguard is built around a slim, lightweight profile, so it favors a trim setup over a bulkier handguard with more external surface area.
- This complete upper is offered with either a 12" or 15" M-LOK ATLAS S-ONE handguard, so the final configuration depends on the selected option rather than a single fixed setup.
- The product listing references both 16" 5.56 mid CMV barrel and 18" rifle barrel options, which means buyers need to confirm the exact configuration before ordering.
- The included low-profile gas block and gas tube are dependent on the chosen barrel length, so the upper is not a one-size-fits-all package.
Suggested Comparisons
- Complete upper receiver assemblies
- Lightweight AR-15 handguard setups
- M-LOK handguard systems
- 16-inch 5.56 upper receiver configurations
Suggested Accessories
- M-LOK accessories
- Backup iron sights
- Weapon light
- Sling
Frequently Asked Questions
What comes included with this upper receiver assembly?
The product description says this is a complete upper that includes Aero Precision's ATLAS S-ONE handguard, an M4E1 threaded assembled upper receiver, and a 16" 5.56 mid CMV barrel. It also notes a low profile gas block and a mid-length gas tube, depending on the configuration.
What handguard options are listed for this upper?
The source data lists a choice of 12" or 15" M-LOK ATLAS S-ONE handguard. The product title shown here specifies the 15" M-Lok Atlas S-One handguard.
Is this upper set up for a lightweight build?
Yes. The description says the S-ONE line of handguards is designed with size and weight in mind and is intended as a fit for a lightweight build.
What caliber is this upper chambered for?
The listed barrel is a 16" 5.56 Mid CMV barrel, so the product is described as a 5.56 upper.
Does the description specify the gas system details?
Yes, but only in general terms. The short description mentions a low profile gas block and a mid-length gas tube, depending on the configuration. It does not provide additional gas system details beyond that.