
Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1-T 6.5 Grendel upper receiver in FDE is a complete, assembled upper built to stretch the effective range of your AR15 platform rifle. This isn't a basic upper swap—it's a purpose-built DMR (Designated Marksman Rifle) configuration with a 20-inch stainless barrel, rifle-length gas system, and the proven 6.5 Grendel cartridge. If you're serious about precision shooting beyond typical intermediate distances or want a low-recoil, high-accuracy option that leverages the AR15's modularity, this is a plug-and-play solution that ships ready to mount on any mil-spec lower receiver.
The M4E1-T upper receiver features Aero's enhanced forging that mimics a billet profile while maintaining the durability of a forged design. It comes with port door and forward assist pre-installed, M4 feedramps for reliable feeding, and laser-engraved T-marks for reference. The 20-inch DMR-profile barrel is 416R stainless steel with a 1/8 twist rate, 5/8x24 threading for sound suppressors or muzzle devices, and a .750 journal for compatibility with low-profile gas blocks. The included .750 low-profile gas block and rifle-length gas tube are sized and tuned for the 6.5 Grendel's ballistics. An A2-style flash hider comes installed; replace it with any 5/8x24 compatible brake or can if your mission demands it.
The integrated ATLAS R-ONE handguard is Aero's slim, no-frills approach to rail real estate—full-length picatinny on top and quick-disconnect sling mounting at 3, 6, and 9 o'clock positions. It's light, stays out of the way, and gives you attachment points without adding unnecessary bulk. Note: you'll need to source a 6.5 Grendel-specific bolt carrier group and magazine separately; the rest of your AR15 setup (stock, grip, trigger group) works as-is. HP and MPI tested barrel ensures reliability and consistency downrange.
| Caliber | 6.5 Grendel |
| Barrel Length | 20 inches |
| Barrel Material | 416R Stainless Steel |
| Barrel Profile | DMR |
| Barrel Twist Rate | 1/8 |
| Gas System | Rifle Length |
| Gas Block | .750 Low Profile |
| Muzzle Threading | 5/8x24 |
| Upper Receiver | M4E1-T Threaded, Forged |
| Handguard | ATLAS R-ONE |
| Handguard Diameter | 1.3" ID / 1.5" OD |
| Finish | Flat Dark Earth (FDE) |
| Configuration | Assembled; does not include BCG or charging handle |
Yes. The M4E1-T upper is compatible with any mil-spec AR15 lower receiver. The .250 takedown pin holes match standard AR15 lowers, so assembly is straightforward.
You'll need a 6.5 Grendel-specific bolt carrier group and 6.5 Grendel magazine. A charging handle is also required. All other AR15 components—lower receiver, fire control group, stock, grip—are standard mil-spec and not included with this upper.
Yes. The barrel is threaded 5/8x24, which is the standard for suppressors designed to work with the 6.5 Grendel. Simply unscrew the installed A2 flash hider and attach your suppressor or muzzle device.
The 6.5 Grendel is a low-recoil, high-accuracy rifle cartridge designed for the AR15 platform. It's engineered for precision at extended ranges and has proven effective at distances of 1000+ yards, making it ideal for DMR builds, long-range hunting, and precision rifle applications.

SKU: 167528977 • Weight: 5oz





Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1-T 6.5 Grendel upper receiver in FDE is a complete, assembled upper built to stretch the effective range of your AR15 platform rifle. This isn't a basic upper swap—it's a purpose-built DMR (Designated Marksman Rifle) configuration with a 20-inch stainless barrel, rifle-length gas system, and the proven 6.5 Grendel cartridge. If you're serious about precision shooting beyond typical intermediate distances or want a low-recoil, high-accuracy option that leverages the AR15's modularity, this is a plug-and-play solution that ships ready to mount on any mil-spec lower receiver.
The M4E1-T upper receiver features Aero's enhanced forging that mimics a billet profile while maintaining the durability of a forged design. It comes with port door and forward assist pre-installed, M4 feedramps for reliable feeding, and laser-engraved T-marks for reference. The 20-inch DMR-profile barrel is 416R stainless steel with a 1/8 twist rate, 5/8x24 threading for sound suppressors or muzzle devices, and a .750 journal for compatibility with low-profile gas blocks. The included .750 low-profile gas block and rifle-length gas tube are sized and tuned for the 6.5 Grendel's ballistics. An A2-style flash hider comes installed; replace it with any 5/8x24 compatible brake or can if your mission demands it.
The integrated ATLAS R-ONE handguard is Aero's slim, no-frills approach to rail real estate—full-length picatinny on top and quick-disconnect sling mounting at 3, 6, and 9 o'clock positions. It's light, stays out of the way, and gives you attachment points without adding unnecessary bulk. Note: you'll need to source a 6.5 Grendel-specific bolt carrier group and magazine separately; the rest of your AR15 setup (stock, grip, trigger group) works as-is. HP and MPI tested barrel ensures reliability and consistency downrange.
| Caliber | 6.5 Grendel |
| Barrel Length | 20 inches |
| Barrel Material | 416R Stainless Steel |
| Barrel Profile | DMR |
| Barrel Twist Rate | 1/8 |
| Gas System | Rifle Length |
| Gas Block | .750 Low Profile |
| Muzzle Threading | 5/8x24 |
| Upper Receiver | M4E1-T Threaded, Forged |
| Handguard | ATLAS R-ONE |
| Handguard Diameter | 1.3" ID / 1.5" OD |
| Finish | Flat Dark Earth (FDE) |
| Configuration | Assembled; does not include BCG or charging handle |
Yes. The M4E1-T upper is compatible with any mil-spec AR15 lower receiver. The .250 takedown pin holes match standard AR15 lowers, so assembly is straightforward.
You'll need a 6.5 Grendel-specific bolt carrier group and 6.5 Grendel magazine. A charging handle is also required. All other AR15 components—lower receiver, fire control group, stock, grip—are standard mil-spec and not included with this upper.
Yes. The barrel is threaded 5/8x24, which is the standard for suppressors designed to work with the 6.5 Grendel. Simply unscrew the installed A2 flash hider and attach your suppressor or muzzle device.
The 6.5 Grendel is a low-recoil, high-accuracy rifle cartridge designed for the AR15 platform. It's engineered for precision at extended ranges and has proven effective at distances of 1000+ yards, making it ideal for DMR builds, long-range hunting, and precision rifle applications.
SKU: 167528977 • Weight: 5oz
