
Availability: In Stock
Current Stock: Out of stock
The Aero M4E1-T complete upper receiver is a ready-to-run 16-inch 5.56 NATO upper built around Aero Precision's proven M4E1 platform. This is a solid choice for shooters who want a quality assembled upper without the hassle of sourcing and fitting individual components—just add a bolt carrier group and charging handle, and you're ready to go. The HBAR barrel profile provides additional mass for reduced recoil impulse and better thermal stability during sustained fire, making it a practical option for range work, tactical training, and general-purpose shooting.
The upper itself is forged 7075-T6 aluminum and precision-machined to Aero's M4E1 specifications, with M4 feedramps, a hard-coat anodized matte black finish, and laser-engraved T-marks for reference. It comes fully assembled with port door and forward assist installed. The included 15-inch ATLAS R-One M-LOK handguard gives you a modern, modular platform with full top picatinny rail real estate, quick-disconnect sling mounts at the 3, 6, and 9 o'clock positions, and traditional M-LOK slots for accessories. The handguard is compatible with standard AR15 uppers and accepts most BAR-system options if you want flexibility down the road.
Your 16-inch HBAR barrel is made from 4150 CrMoV steel with QPQ corrosion resistance, features a 1/7 twist rate, and wears a standard A2 flash hider. It's paired with a mid-length gas system and low-profile gas block tuned to the barrel's .750-inch journal. Both the barrel and bolt carrier group journal have been HP and MPI tested for reliability. The package includes the barrel nut and wrench; just remember that a bolt carrier group and charging handle are sold separately.
| Upper Receiver Material | 7075-T6 Forged Aluminum |
| Finish | Matte Black Hard-Coat Anodized (Mil 8625 Type 3 Class 2) |
| Barrel Caliber | 5.56 NATO |
| Barrel Length | 16 inches |
| Barrel Material | 4150 CrMoV with QPQ |
| Barrel Twist Rate | 1/7 |
| Gas System | Mid-Length |
| Gas Block Profile | Low-Profile (.750 inch journal) |
| Muzzle Device | A2 Flash Hider |
| Handguard Type | ATLAS R-One M-LOK, 15 inches |
| Handguard Inner Diameter | 1.3 inches |
| Handguard Outer Diameter | 1.5 inches |
| Top Rail | Full-length Picatinny |
| QD Sling Mounts | 3, 6, 9 o'clock positions |
| Assembly Status | Fully Assembled |
| Includes | Barrel Nut and Wrench |
| Does Not Include | Bolt Carrier Group, Charging Handle |
You'll need a bolt carrier group and a charging handle. This upper receiver comes fully assembled with the barrel, gas system, handguard, and port door already installed—just add those two components and a lower receiver to have a complete rifle.
Yes. The M4E1 upper receiver accepts standard AR15 and M16 components. The ATLAS R-One handguard is compatible with mil-spec AR15 upper receivers and also fits most BAR-system handguards if you decide to swap it out later.
The HBAR profile barrel is heavier and thicker than a carbine or government-profile barrel, which helps reduce recoil impulse and keeps the barrel cooler during sustained fire. It's a practical choice for range sessions and tactical training where thermal management matters.
The barrel is made from 4150 CrMoV steel with QPQ corrosion resistance, which provides good protection against rust and wear. Standard rifle barrel maintenance—cleaning and dry storage—will keep it in good shape. The QPQ finish is durable and doesn't require special treatment compared to other military-grade barrels.

SKU: 126797500 • Weight: 4.3oz
Availability: In Stock
Current Stock: Out of stock
The Aero M4E1-T complete upper receiver is a ready-to-run 16-inch 5.56 NATO upper built around Aero Precision's proven M4E1 platform. This is a solid choice for shooters who want a quality assembled upper without the hassle of sourcing and fitting individual components—just add a bolt carrier group and charging handle, and you're ready to go. The HBAR barrel profile provides additional mass for reduced recoil impulse and better thermal stability during sustained fire, making it a practical option for range work, tactical training, and general-purpose shooting.
The upper itself is forged 7075-T6 aluminum and precision-machined to Aero's M4E1 specifications, with M4 feedramps, a hard-coat anodized matte black finish, and laser-engraved T-marks for reference. It comes fully assembled with port door and forward assist installed. The included 15-inch ATLAS R-One M-LOK handguard gives you a modern, modular platform with full top picatinny rail real estate, quick-disconnect sling mounts at the 3, 6, and 9 o'clock positions, and traditional M-LOK slots for accessories. The handguard is compatible with standard AR15 uppers and accepts most BAR-system options if you want flexibility down the road.
Your 16-inch HBAR barrel is made from 4150 CrMoV steel with QPQ corrosion resistance, features a 1/7 twist rate, and wears a standard A2 flash hider. It's paired with a mid-length gas system and low-profile gas block tuned to the barrel's .750-inch journal. Both the barrel and bolt carrier group journal have been HP and MPI tested for reliability. The package includes the barrel nut and wrench; just remember that a bolt carrier group and charging handle are sold separately.
| Upper Receiver Material | 7075-T6 Forged Aluminum |
| Finish | Matte Black Hard-Coat Anodized (Mil 8625 Type 3 Class 2) |
| Barrel Caliber | 5.56 NATO |
| Barrel Length | 16 inches |
| Barrel Material | 4150 CrMoV with QPQ |
| Barrel Twist Rate | 1/7 |
| Gas System | Mid-Length |
| Gas Block Profile | Low-Profile (.750 inch journal) |
| Muzzle Device | A2 Flash Hider |
| Handguard Type | ATLAS R-One M-LOK, 15 inches |
| Handguard Inner Diameter | 1.3 inches |
| Handguard Outer Diameter | 1.5 inches |
| Top Rail | Full-length Picatinny |
| QD Sling Mounts | 3, 6, 9 o'clock positions |
| Assembly Status | Fully Assembled |
| Includes | Barrel Nut and Wrench |
| Does Not Include | Bolt Carrier Group, Charging Handle |
You'll need a bolt carrier group and a charging handle. This upper receiver comes fully assembled with the barrel, gas system, handguard, and port door already installed—just add those two components and a lower receiver to have a complete rifle.
Yes. The M4E1 upper receiver accepts standard AR15 and M16 components. The ATLAS R-One handguard is compatible with mil-spec AR15 upper receivers and also fits most BAR-system handguards if you decide to swap it out later.
The HBAR profile barrel is heavier and thicker than a carbine or government-profile barrel, which helps reduce recoil impulse and keeps the barrel cooler during sustained fire. It's a practical choice for range sessions and tactical training where thermal management matters.
The barrel is made from 4150 CrMoV steel with QPQ corrosion resistance, which provides good protection against rust and wear. Standard rifle barrel maintenance—cleaning and dry storage—will keep it in good shape. The QPQ finish is durable and doesn't require special treatment compared to other military-grade barrels.
SKU: 126797500 • Weight: 4.3oz
