AeroPrecision167527212
M4E1 5.56 Nato Assem Uppr Rcvr M4 10.5'' Bbl Carbine Black$571.76
Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1 5.56 assembled upper receiver is a fully-built upper designed for shooters who want to complete their AR-15 build with quality components already installed and tested. This carbine upper comes with a 10.5\" barrel, carbine-length gas system, and a 7" handguard with front sight base—everything except the bolt carrier group and charging handle, which are intentionally left out so you can choose those parts to match your build. Whether you're assembling a compact AR pistol or planning an SBR (with proper NFA registration), the 10.5" barrel length delivers the versatility serious builders expect in a purpose-built upper receiver.
At the core is Aero's forged M4E1 receiver, which pairs the ergonomic, billet-style profile with true mil-spec compatibility for BCGs and charging handles. The 4150 chrome-moly-vanadium barrel is chambered in 5.56 NATO and safely handles .223 Remington as well, with 1-7\" rifling for reliable bullet stabilization across both cartridges. The A2 flash suppressor comes installed (unfastened, not pinned) and the handguard's 1.78" bore clears most muzzle devices and suppressors you'll want to run. Black QPQ finish on the barrel and Parkerized steel parts resist corrosion in the field, while the 7075 T6 forged aluminum receiver delivers durability without the weight.
The included Gen 2 Enhanced M-LOK handguard creates a monolithic mounting platform with full-length top Picatinny rail and M-LOK slots at multiple positions for accessory mounting. Textured grip flats on the receiver add purchase and visual character. QD sling attachment points at 3, 6, and 9 o'clock give you flexible carry and deployment options. This is a straightforward, no-compromise upper receiver built for hunters, precision shooters, and AR builders who refuse to compromise on fit, finish, or function.
| Brand | Aero Precision |
| Product Type | Assembled Upper Receiver |
| Caliber | 5.56 NATO / .223 Remington |
| Barrel Length | 10.5\" |
| Barrel Material | 4150 Chrome-Moly-Vanadium |
| Barrel Rifling | 1-7\" twist |
| Gas System | Carbine-length |
| Receiver Material | Forged 7075 T6 Aluminum |
| Receiver Finish | Mil 8625 Type 3 Class 2 hardcoat anodized |
| Receiver Style | M4E1 (mil-spec compatible) |
| Handguard Length | 7\" |
| Handguard Style | Gen 2 Enhanced M-LOK |
| Handguard Bore Diameter | 1.78\" |
| Gas Block Type | Front Sight Base |
| Top Rail | Full-length Picatinny |
| Muzzle Device | A2 Flash Suppressor (installed, not pinned) |
| Not Included | Bolt Carrier Group, Charging Handle |
You'll need a bolt carrier group and charging handle to finish the build. Both are intentionally left off so you can choose components that match your preferences and budget. Everything else—barrel, gas system, handguard, and rail system—comes installed and ready to go.
Yes. The 10.5" barrel length and carbine-length gas system work for both configurations. If you're building an SBR, you'll need to follow all applicable NFA regulations and obtain the proper federal tax stamp and registration before assembly.
The handguard's 1.78\" inside diameter clears most suppressors up to 1.5" in diameter, so you have good options. Always verify your specific suppressor's dimensions before installation.
The barrel is chambered in 5.56 NATO and safely handles both 5.56 NATO and .223 Remington ammunition. The 1-7\" rifling stabilizes a wide range of bullet weights in both cartridges.
No. The A2 flash suppressor comes installed but not pinned or welded, so you can remove or replace it if you prefer a different muzzle device.
SKU: 167528949 • Weight: 3.6oz
Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1 5.56 assembled upper receiver is a fully-built upper designed for shooters who want to complete their AR-15 build with quality components already installed and tested. This carbine upper comes with a 10.5\" barrel, carbine-length gas system, and a 7" handguard with front sight base—everything except the bolt carrier group and charging handle, which are intentionally left out so you can choose those parts to match your build. Whether you're assembling a compact AR pistol or planning an SBR (with proper NFA registration), the 10.5" barrel length delivers the versatility serious builders expect in a purpose-built upper receiver.
At the core is Aero's forged M4E1 receiver, which pairs the ergonomic, billet-style profile with true mil-spec compatibility for BCGs and charging handles. The 4150 chrome-moly-vanadium barrel is chambered in 5.56 NATO and safely handles .223 Remington as well, with 1-7\" rifling for reliable bullet stabilization across both cartridges. The A2 flash suppressor comes installed (unfastened, not pinned) and the handguard's 1.78" bore clears most muzzle devices and suppressors you'll want to run. Black QPQ finish on the barrel and Parkerized steel parts resist corrosion in the field, while the 7075 T6 forged aluminum receiver delivers durability without the weight.
The included Gen 2 Enhanced M-LOK handguard creates a monolithic mounting platform with full-length top Picatinny rail and M-LOK slots at multiple positions for accessory mounting. Textured grip flats on the receiver add purchase and visual character. QD sling attachment points at 3, 6, and 9 o'clock give you flexible carry and deployment options. This is a straightforward, no-compromise upper receiver built for hunters, precision shooters, and AR builders who refuse to compromise on fit, finish, or function.
| Brand | Aero Precision |
| Product Type | Assembled Upper Receiver |
| Caliber | 5.56 NATO / .223 Remington |
| Barrel Length | 10.5\" |
| Barrel Material | 4150 Chrome-Moly-Vanadium |
| Barrel Rifling | 1-7\" twist |
| Gas System | Carbine-length |
| Receiver Material | Forged 7075 T6 Aluminum |
| Receiver Finish | Mil 8625 Type 3 Class 2 hardcoat anodized |
| Receiver Style | M4E1 (mil-spec compatible) |
| Handguard Length | 7\" |
| Handguard Style | Gen 2 Enhanced M-LOK |
| Handguard Bore Diameter | 1.78\" |
| Gas Block Type | Front Sight Base |
| Top Rail | Full-length Picatinny |
| Muzzle Device | A2 Flash Suppressor (installed, not pinned) |
| Not Included | Bolt Carrier Group, Charging Handle |
You'll need a bolt carrier group and charging handle to finish the build. Both are intentionally left off so you can choose components that match your preferences and budget. Everything else—barrel, gas system, handguard, and rail system—comes installed and ready to go.
Yes. The 10.5" barrel length and carbine-length gas system work for both configurations. If you're building an SBR, you'll need to follow all applicable NFA regulations and obtain the proper federal tax stamp and registration before assembly.
The handguard's 1.78\" inside diameter clears most suppressors up to 1.5" in diameter, so you have good options. Always verify your specific suppressor's dimensions before installation.
The barrel is chambered in 5.56 NATO and safely handles both 5.56 NATO and .223 Remington ammunition. The 1-7\" rifling stabilizes a wide range of bullet weights in both cartridges.
No. The A2 flash suppressor comes installed but not pinned or welded, so you can remove or replace it if you prefer a different muzzle device.
SKU: 167528949 • Weight: 3.6oz