AeroPrecision167527269
M4E1-T 6.5 Grendel Assem Upper Spr 18''Bbl Rifle Threaded Blk$701.49
Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1-T 6.5 Grendel complete upper receiver brings serious reach and accuracy to your AR15 platform build. Chambered in 6.5 Grendel—a cartridge engineered for low recoil and high precision—this 18-inch rifle-length upper is built to stretch beyond typical AR15 distances without the punishing kick of a magnum round. Whether you're setting up a precision rifle for backcountry hunting, a competition rig, or a dedicated range gun, this assembly gives you a proven platform capable of reliable performance where it counts.
This complete upper arrives fully assembled and ready to mount, featuring Aero Precision's M4E1 threaded upper receiver paired with the company's ATLAS R-ONE handguard. The R-ONE strikes a practical balance: a slim, lightweight aluminum tube that doesn't sacrifice real estate for optics, lights, or other accessories. Its three-position quick-disconnect sling attachment points and full-length top picatinny rail make it flexible for whatever your mission demands. The 18-inch 416R stainless steel barrel wears a rifle-length gas system with a .750 low-profile gas block and A2-style flash hider, all pressure-tested to Aero's standards.
Keep in mind: this upper does not include a bolt carrier group or charging handle—you'll need to source those separately along with a 6.5 Grendel-specific bolt and magazines. Everything else lives in the standard AR15 ecosystem, so if you already run AR15 lowers and accessories, integrating this upper into your build is straightforward. The M4E1 receiver features M4 feed ramps, laser-engraved T-marks for sight alignment, and the enhanced forging profile Aero is known for.
| Caliber | 6.5 Grendel |
| Barrel Length | 18 inches |
| Barrel Material | 416R Stainless Steel |
| Barrel Profile | SPR |
| Twist Rate | 1/8 |
| Gas System | Rifle Length |
| Gas Block | .750 Low Profile |
| Muzzle Device | A2-style Flash Hider |
| Threaded Pitch | 5/8x24 |
| Handguard | ATLAS R-ONE |
| Handguard ID | 1.3 inches |
| Handguard OD | 1.5 inches |
| Upper Receiver | Aero Precision M4E1-T (threaded) |
| Feed Ramps | M4 |
| Finish | Flat Dark Earth (FDE) |
| Assembled | Yes |
This upper assembly requires a bolt carrier group, charging handle, and a 6.5 Grendel-specific bolt and magazine—these are not included. You can use your existing AR15 lower receiver; the upper will bolt directly to any mil-spec lower.
Yes. The barrel is threaded 5/8x24, which is the standard for suppressors in this caliber. You'll need a suppressor rated for 6.5 Grendel.
6.5 Grendel is designed as a low-recoil, high-accuracy cartridge that extends your effective range well beyond standard 5.56 NATO. It's proven for accuracy-focused shooting and hunting where you need better ballistics and less recoil than larger magnum rounds.
Yes. The R-ONE is designed to work with low-profile gas blocks, and this upper includes a .750 low-profile block from the factory.
SKU: 167527267 • Weight: 5oz
Availability: In Stock
Current Stock: Out of stock
The Aero Precision M4E1-T 6.5 Grendel complete upper receiver brings serious reach and accuracy to your AR15 platform build. Chambered in 6.5 Grendel—a cartridge engineered for low recoil and high precision—this 18-inch rifle-length upper is built to stretch beyond typical AR15 distances without the punishing kick of a magnum round. Whether you're setting up a precision rifle for backcountry hunting, a competition rig, or a dedicated range gun, this assembly gives you a proven platform capable of reliable performance where it counts.
This complete upper arrives fully assembled and ready to mount, featuring Aero Precision's M4E1 threaded upper receiver paired with the company's ATLAS R-ONE handguard. The R-ONE strikes a practical balance: a slim, lightweight aluminum tube that doesn't sacrifice real estate for optics, lights, or other accessories. Its three-position quick-disconnect sling attachment points and full-length top picatinny rail make it flexible for whatever your mission demands. The 18-inch 416R stainless steel barrel wears a rifle-length gas system with a .750 low-profile gas block and A2-style flash hider, all pressure-tested to Aero's standards.
Keep in mind: this upper does not include a bolt carrier group or charging handle—you'll need to source those separately along with a 6.5 Grendel-specific bolt and magazines. Everything else lives in the standard AR15 ecosystem, so if you already run AR15 lowers and accessories, integrating this upper into your build is straightforward. The M4E1 receiver features M4 feed ramps, laser-engraved T-marks for sight alignment, and the enhanced forging profile Aero is known for.
| Caliber | 6.5 Grendel |
| Barrel Length | 18 inches |
| Barrel Material | 416R Stainless Steel |
| Barrel Profile | SPR |
| Twist Rate | 1/8 |
| Gas System | Rifle Length |
| Gas Block | .750 Low Profile |
| Muzzle Device | A2-style Flash Hider |
| Threaded Pitch | 5/8x24 |
| Handguard | ATLAS R-ONE |
| Handguard ID | 1.3 inches |
| Handguard OD | 1.5 inches |
| Upper Receiver | Aero Precision M4E1-T (threaded) |
| Feed Ramps | M4 |
| Finish | Flat Dark Earth (FDE) |
| Assembled | Yes |
This upper assembly requires a bolt carrier group, charging handle, and a 6.5 Grendel-specific bolt and magazine—these are not included. You can use your existing AR15 lower receiver; the upper will bolt directly to any mil-spec lower.
Yes. The barrel is threaded 5/8x24, which is the standard for suppressors in this caliber. You'll need a suppressor rated for 6.5 Grendel.
6.5 Grendel is designed as a low-recoil, high-accuracy cartridge that extends your effective range well beyond standard 5.56 NATO. It's proven for accuracy-focused shooting and hunting where you need better ballistics and less recoil than larger magnum rounds.
Yes. The R-ONE is designed to work with low-profile gas blocks, and this upper includes a .750 low-profile block from the factory.
SKU: 167527267 • Weight: 5oz