.338 ARC Uppers and Parts for AR-15 – Moriarti Arms

High-Energy Subsonic and Supersonic Builds for the Modern AR-15

Unlock the power of the .338 ARC with premium AR-15 parts and complete uppers from Moriarti Arms. Designed for subsonic and long-range performance, the .338 ARC delivers big-bore energy in a compact, low-recoil platform. All Moriarti .338 ARC components are fully compatible with 6.5 Grendel Type II bolts, making them ideal for hunters, suppressor users, and tactical shooters alike. From precision-machined .338 ARC barrels to fully assembled .338 ARC upper receivers, our inventory is built for reliability and power. Explore our full collection of .338 ARC uppers by Moriarti Arms and Grendel-compatible bolt carrier groups to create your next suppressed or supersonic AR-15 build.