.400 Legend Upper Assembly | Precision and Power by Moriarti Armaments

.400 Legend Uppers

Upgrade your AR-15 with a premium .400 Legend AR Upper from Moriarti Armaments. Designed for shooters seeking a powerful straight-wall cartridge, our complete .400 Legend Upper assemblies combine premium USA-made components, free-float M-LOK handguards, and precision barrels for dependable performance in the field or at the range. Built around the versatile AR-15 platform, our uppers are ideal for hunters in straight-wall cartridge states, recreational shooters, and custom builders looking for increased power while maintaining the familiar ergonomics and modularity of the AR-15.

What is a .400 Legend AR Upper best used for?

A .400 Legend AR Upper is designed for shooters who want the performance of the .400 Legend cartridge on the AR-15 platform. It is particularly popular for hunting in states that require straight-wall cartridges, while also offering excellent performance for recreational shooting and custom AR builds. Compatible with Mil-Spec AR-15 lower receivers when paired with the correct caliber-specific components, it provides a powerful alternative to traditional intermediate AR cartridges.