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M4e1 5.56mm Assembled Upper Receiver W/Gen-2 Handguard & Fsb - M4e1 5.56 Assm Uppr Rcvr Gov 10.5'''' Bbl Carbine W/7''''hg & Fsb
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$554.99
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SKU: 100025504
Overview
This assembled upper receiver is built for shooters putting together an AR pistol or SBR and want a ready-to-fit top half with room to choose their own bolt carrier group and charging handle. It pairs Aero Precision’s forged M4E1 receiver with a proprietary handguard attachment system and an included 7-inch handguard, while keeping compatibility with standard mil-spec components. The 10.5-inch barrel is chambered for 5.56mm NATO and is also suitable for .223 Remington ammunition. It is a practical option for compact builds where a fully assembled upper can simplify the setup process without locking in the final internal components.
Why Hunters Choose the Aero Precision
Fully Assembled
Upper receiver saves time on
Includes Aero's
Mil-spec parts compatibility
Proprietary Handguard
Attachment system is already installed
Chambered 5.56mm
.223 Remington ammo
Lacks Only
Bolt/carrier group and charging handle
Key Features
- Fully assembled upper receiver; bolt carrier group and charging handle sold separately
- Forged M4E1 receiver with custom billet-style appearance
- Mil-spec parts compatibility, including BCG and charging handle
- Includes Aero's proprietary handguard attachment system
- 10.5-inch carbine upper chambered for 5.56mm NATO
- Safely handles civilian .223 Remington ammunition
Best Used For
- AR pistol or SBR builders wanting a fully assembled upper with room for personal component selection
- Hunters and shooters needing a compact 10.5-inch carbine upper for short-barrel setups
- Users who want mil-spec parts compatibility while keeping the M4E1 receiver and handguard system
- Builders prioritizing a complete top-half assembly without a bolt carrier group or charging handle
Specifications
| Assembly Status | Fully assembled |
|---|---|
| Attachment System | Proprietary attachment system |
| Barrel Length | 10.5" |
| Barrel Material | 4150 chrome-moly-vanadium carbon steel |
| Barrel Profile | Government |
| Caliber | 5.56mm |
| Chambering | 5.56mm NATO |
| Compatible Ammunition | .223 Remington |
| Excluded Components | Bolt/carrier group |
| Excluded Components 2 | Charging handle |
| Front Sight Base | Included |
| Handguard | Gen-2 handguard |
| Handguard Length | 7" |
| Included Components | Upper receiver with handguard and front sight base |
| Mil Spec Compatibility | BCG and charging handle compatible |
| Upper Receiver | Forged M4E1 receiver |
Pros
- Fully assembled upper receiver saves time on AR pistol or SBR setup.
- Includes Aero's forged M4E1 receiver with mil-spec parts compatibility.
- Proprietary handguard attachment system is already installed.
- Chambered for 5.56mm NATO and compatible with .223 Remington ammo.
- Lacks only bolt/carrier group and charging handle for customization.
Considerations & Trade-offs
- This is a complete upper assembly only; a bolt carrier group and charging handle still need to be selected separately.
- The 10.5-inch carbine configuration is geared toward AR pistol or SBR builds, so it is not a full-length setup.
- The included handguard uses Aero’s proprietary attachment system, which may matter if you prefer a more standard handguard interface.
- Chambered for 5.56mm NATO, it can also use .223 Remington, but the build is centered on that caliber family rather than broader cartridge flexibility.
Suggested Comparisons
- AR pistol upper receivers
- SBR upper receivers
- Complete upper receiver assemblies
- AR handguards and rail systems
Suggested Accessories
- Bolt carrier group
- Charging handle
- AR pistol brace
- Sling
Frequently Asked Questions
What comes included with this upper receiver assembly?
It comes fully assembled and includes the upper receiver, barrel, and the included handguard. It does not include a bolt carrier group or charging handle.
Is this upper compatible with standard AR parts?
Yes. The description says the forged M4E1 receiver maintains mil-spec parts compatibility, including the BCG and charging handle.
What ammunition is this upper chambered for?
It is chambered for 5.56mm NATO ammunition and is also stated to safely handle civilian .223 Remington ammo.
Is this intended for a pistol or SBR build?
The short description identifies it as a top half for an AR pistol or SBR.
Does the product description specify the handguard length?
Yes, the title lists a 7" handguard, and the description says the upper uses Aero's proprietary attachment system for the included handguard.