AR-15 Upper Assemblies

Moriarti's AR-15 Upper Assemblies for Custom Builds & Upgrades

Discover AR-15 upper assemblies from Moriarti Armaments, built for shooters seeking quality, reliability, and performance. Our collection includes complete and stripped upper assemblies in popular calibers such as 5.56 NATO, .223 Wylde, 300 AAC Blackout, 7.62x39, 6MM ARC, 6.5 Grendel, .350 Legend, .450 Bushmaster, .50 Beowulf, .22 LR, and more. Choose from a variety of barrel lengths, handguard styles, muzzle devices, and finishes to build or upgrade your AR-15. Whether you're looking for a compact pistol upper, a carbine configuration, or a full-size rifle upper, Moriarti Armaments offers options compatible with most standard mil-spec AR-15 lower receivers.

How do I know which AR-15 upper assembly is compatible with my lower receiver?

Most standard AR-15 upper assemblies are designed around the common AR-15 receiver pattern, but compatibility depends on more than the receiver itself. Check the caliber, bolt carrier group, magazine requirements, buffer system, gas system, and any caliber-specific components listed for the upper. Some AR-15 calibers can use a standard lower receiver while requiring different magazines, bolts, or other components. Always verify the specifications of the upper and your existing firearm components before purchasing.