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Ar-15/M4 Flattop Upper Receiver Assembly - Upper Receiver Assembly
Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.
$129.00
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SKU: 100014626
Overview
This forged aluminum flattop receiver assembly is built to serve as the foundation for an AR-15/M4 upper, with a fully assembled forward assist and ejection port cover already in place. It is machined to mil-spec tolerances and accepts barrels with M4 barrel extensions, making it suited for builders who want a properly fitting component for a standard parts setup. Laser-etched T-marks on the Picatinny rail help return optics, sights, and other accessories to the same position after removal, while the interior dry film lubrication is included to help reduce wear. The receiver is hardcoat anodized in matte black and uses .250" pivot/takedown pin holes, but the tighter barrel-extension fit may require warming the threaded bore if installation is snug.
Why Hunters Choose the Bravo Company
Forged Aluminum
Fully assembled forward assist and
Accepts Barrels
M4 barrel extensions for standard
Machined Mil-spec
Tolerances to readily accept standard
Laser-etched T-marks
On the Picatinny rail support
Interior Dry
Film lubrication and hardcoat anodized
Key Features
- Forged aluminum flattop receiver with fully assembled forward assist and ejection port cover.
- Accepts barrels with M4 barrel extensions.
- Machined to correct mil-spec tolerances for standard AR-15 parts compatibility.
- Laser-etched T-marks on the Picatinny rail for optic and accessory repositioning.
- Interior dry film lubrication helps reduce wear.
- 7075 T6 aluminum construction with hardcoat anodized matte black finish.
- .250" pivot/takedown pin holes.
Best Used For
- AR-15 builders needing a flattop upper receiver assembly for a standard parts-compatible project
- Hunters setting up optics and accessories with repeatable rail positioning using laser-etched T-marks
- Users assembling an upper around barrels with M4 barrel extensions and mil-spec dimensions
- Shooters who want a fully assembled receiver with forward assist and ejection port cover included
Specifications
| Barrel Compatibility | accepts barrels with M4 barrel extensions |
|---|---|
| Barrel Extension Fit | slightly undersized inside diameter for tighter fit |
| Blade Finish | hardcoat anodized |
| Color | matte black |
| Ejection Port Cover | fully-assembled |
| Forward Assist | fully-assembled |
| Interior Coating | dry film lubrication |
| Material | 7075 T6 aluminum |
| Mil Spec Tolerances | correct mil-spec tolerances |
| Pivottakedown Pin Hole Size | .250" (6.3mm) |
| Receiver Type | flattop upper receiver assembly |
| T Marks | laser-etched T-marks on Picatinny rail |
| Threaded Bore Warm Up Note | use a hair dryer to warm up threaded bore if barrel extension is too tight |
Pros
- Forged aluminum flattop receiver with fully assembled forward assist and ejection port cover.
- Accepts barrels with M4 barrel extensions for standard AR-15 upper assembly compatibility.
- Machined to mil-spec tolerances to readily accept standard AR-15 parts.
- Laser-etched T-marks on the Picatinny rail support repeatable optic and accessory placement.
- Interior dry film lubrication and hardcoat anodized finish are included in the specifications.
Considerations & Trade-offs
- Requires a separate barrel and other upper components; this is an upper receiver assembly, not a complete upper or rifle.
- The barrel extension fit is intentionally slightly undersized, so installation may need warming the threaded bore if the fit is too tight.
- Compatibility is specific to barrels with M4 barrel extensions and standard AR-15 parts, so it is not a universal receiver for every setup.
- The matte black hardcoat anodized finish is functional and subdued rather than decorative or highly reflective.
Suggested Comparisons
- AR-15 upper receiver assemblies
- AR-15 upper receiver parts
- AR-15 build components
- Picatinny rail accessories
Suggested Accessories
- AR-15 upper receiver parts kit
- Picatinny rail accessories
- Optics mounts
- Barrel nut wrench
Frequently Asked Questions
What parts are included with this upper receiver assembly?
The description says it includes a fully assembled forward assist and ejection port cover.
What type of barrels will this upper accept?
It accepts barrels with M4 barrel extensions.
What material and finish are listed for this receiver?
The listed specs are 7075 T6 aluminum with a hardcoat anodized, matte black finish.
Are the pivot and takedown pin holes standard size?
The specs list .250" (6.3mm) pivot/takedown pin holes.
Does the product include any rail markings for mounting optics or accessories?
Yes. The Picatinny rail has laser-etched T-marks to help with removal and re-mounting of optics, sights, and other accessories in the correct position.