Bushmaster

Bushmaster XM-15 Complete 5.56x45mm Upper Receiver 16\" Barrel - 00-400003-Black

Bushmaster XM-15 Complete 5.56x45mm Upper Receiver 16\" Barrel - 00-400003-BLK - Upper Receiver for AR-15 - view 1
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Bushmaster

Overview

The Bushmaster XM-15 Complete Upper Receiver features a 16" barrel chambered in 5.56 NATO, making it ideal for a variety of shooting applications. Constructed from 7075-T6 aluminum, this complete assembly is designed for durability while maintaining a lightweight profile, which is essential for optimizing your AR-15 build. This upper receiver is commonly found in builds focused on the 5.56 NATO caliber, providing a reliable option for both range use and home defense.

Specifications

MPN00-400003-BLK
PlatformAR-15
AssemblyComplete
Caliber5.56 NATO
Material7075-T6 Aluminum
Barrel Length16

Available Merchants(1)

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$499.99
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September 2026 on GunPartPicker

Bushmaster XM-15 Complete 5.56x45mm Upper Receiver 16\" Barrel - 00-400003-Black ranked #267 of the 615 upper receivers builders added on GunPartPicker in September 2026. Builders have been adding it to their builds on GunPartPicker since May 2026. All time, it ranks #430 of the 1,794 upper receivers builders have added.

Today the one retailer we track is out of stock. Listed prices start at $499.99 at Classic Firearms for when it comes back.

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Build Configuration Breakdown

Aggregated and anonymized data showing how builders use this product

Gas System

50.2%
Mid-Length50.2%
Carbine25.8%
Pistol11.5%
Rifle10.9%
Blowback1.3%
Other0.3%

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