M4E1-T 6.5 Grendel Assem Upper Dmr 20''Bbl Rifle Threaded Blk

The Aero Precision M4E1-T 6.5 Grendel complete upper receiver with 20-inch DMR barrel is a purpose-built platform for shooters who want serious range capability on the AR15. This isn't a generic upper—it's a complete, assembled package that puts you in the game for extended-distance shooting with a cartridge engineered for low recoil and high accuracy. The 6.5 Grendel has proven itself capable at 1000+ yards, making this upper a solid choice for hunters, precision shooters, and anyone who wants to extend their effective range without fighting excessive kick.

You're getting real quality here. The upper receiver features Aero's enhanced M4E1 forging with that billet-look finish, M4 feedramps, and all the controls you expect—port door, forward assist, and laser-engraved T-marks for quick reference. The 20-inch 416R stainless steel barrel wears a DMR profile with 1/8 twist and comes threaded 5/8x24 for suppressor mounting or muzzle devices. It's set up with rifle-length gas, a .750 low-profile gas block, and an A2-style flash hider, all pre-assembled and ready to mount to a lower receiver. The barrel has been HP and MPI tested for quality assurance.

The ATLAS R-ONE handguard rounds out the package—it's slim and light without sacrificing mounting real estate. Full top picatinny rail, quick-disconnect sling sockets at 3, 6, and 9 o'clock, and compatibility with low-profile gas blocks mean you won't be limited in how you set this rifle up. One heads-up: this upper does not include a bolt carrier group or charging handle, and you'll need a 6.5 Grendel-specific bolt and magazine to complete the build. Everything else locks into standard AR15 dimensions.

Key Features

• 20-inch 416R stainless steel barrel with DMR profile and 1/8 twist—proven for long-range precision
• Threaded 5/8x24 muzzle for suppressors or other muzzle devices
• M4E1-T upper receiver with enhanced forging and billet aesthetic
• Complete assembly: includes low-profile gas block, rifle-length gas tube, and A2 flash hider
• ATLAS R-ONE handguard with full top picatinny rail and QD sling mounts
• HP and MPI tested barrel for reliability and safety
• Port door and forward assist installed
• M4 feedramp compatibility

Specifications

Frequently Asked Questions

Does this upper come fully assembled and ready to mount?

Yes. The M4E1-T upper receiver, barrel, gas block, gas tube, flash hider, and ATLAS R-ONE handguard all come assembled. You'll mount it to a lower receiver. Note that it does not include a bolt carrier group or charging handle—you'll need to source those separately.

What do I need to complete this build?

You'll need a lower receiver, a 6.5 Grendel-specific bolt carrier group and bolt, a 6.5 Grendel magazine, and a charging handle. All other AR15 components and standards apply to this upper.

Is the muzzle threaded, and what size threads are they?

Yes, the barrel is threaded 5/8x24, which is a standard suppressor and muzzle device pitch. It ships with an A2-style flash hider installed.

How is the 6.5 Grendel known to perform at distance?

The 6.5 Grendel is engineered for low recoil and high accuracy and has proven itself capable at 1000+ yards in proven field and range applications.