Aero Precision M4E1 Complete Upper, 13.9″ 5.56 Mid-Length Gov Profile Barrel, 12.7″ MOD 4 Handguard – OD Green
The Aero Precision M4E1 Complete Upper with a 13.9″ 5.56 barrel and 12.7″ MOD 4 Handguard in OD Green is a builder’s favorite for creating a compact rifle that avoids NFA regulations when paired with a properly pinned and welded muzzle device. This upper delivers enhanced ergonomics and full-length rifle capability in a visually distinct anodized OD Green finish.
The 13.9″ barrel is machined from 4150 Chrome Moly Vanadium steel and finished in QPQ Nitride to increase corrosion resistance and lifespan. Its 1:7 twist rate stabilizes a wide range of 5.56 NATO bullet weights, and the carbine-length gas system ensures consistent cycling across various conditions and suppressor use.
The 12.7″ MOD 4 Handguard provides ample space for lights, grips, sling hardware, and backup sights. Its slim, free-floating profile is M-LOK compatible and includes a continuous Picatinny top rail, making it perfect for flexible setups. The length aligns neatly with the 13.9″ barrel for optimal hand placement and accessory integration.
The OD Green M4E1 upper receiver is forged from 7075-T6 aluminum and hardcoat anodized for rugged use. It includes the forward assist and port door as standard, while the Nickel Boron Coated M4 Feed Ramp Extension ensures smooth feeding under sustained use. The muzzle is threaded 1/2×28 and finished with an 11° target crown for enhanced durability.
Compatible with all standard AR15 components and lower receivers, this upper offers a compliant and optimized solution for shooters who want a shorter rifle platform without the paperwork, while maintaining full functionality and aesthetics.
Product Information
Product Type | Upper Receiver, Complete Upper |
---|---|
Material | 4150 Chrome Moly Vanadium, 7075-T6 Aluminum |
Muzzle Thread | 1/2×28 |
Handguard | 12.7" M-LOK |
Series | M4E1, MOD 4 |
Manufacturer | Aero Precision |
Platform | AR15 |
Color | OD Green |
Finish | Anodized |
Caliber | 5.56 NATO |
Length | 13.9" |
Gas System | Mid-Length |
Twist Rate | 1:7 |
Barrel Finish | QPQ Nitride |
Compatibility | Standard AR15 components |
Made in USA | Yes |
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