Moriarti Arms is proud to introduce the .338 ARC, our newest caliber offering engineered for the AR-15 platform. Designed for shooters who demand greater power, precision, and suppressor compatibility, the .338 ARC delivers energy and flexibility unmatched by traditional AR-15 calibers. Built around the reliable 6.5 Grendel Type II bolt face, this round offers enhanced terminal ballistics for hunting and tactical use without requiring an AR-10 upgrade.
For shooters looking to expand their arsenal, the .338 ARC offers exceptional performance in both subsonic and supersonic applications, making it ideal for suppressed builds, hog hunting, or long-range shooting.
Comparing .338 ARC to 6mm ARC and 7.62x39
Choosing the right caliber depends on your specific shooting goals. Below is a performance comparison between the .338 ARC, 6mm ARC, and 7.62x39—all supported by Moriarti Arms.
.338 ARC vs. 6mm ARC
| Feature | .338 ARC | 6mm ARC |
|---|
| Bullet Diameter | .338" | .243" |
| Subsonic Capability | Excellent (ideal for suppression) | Limited |
| Long-Range Accuracy | Moderate, with energy focus | Excellent, flatter trajectory |
| Energy at Distance | High | Medium |
| Best Use | Hunting, suppressed builds | Precision target shooting |
| For suppressed hunting and heavy-hitting performance, the .338 ARC upper receivers from Moriarti Arms are the superior choice. |
.338 ARC vs. 7.62x39
| Feature | .338 ARC | 7.62x39 |
|---|
| Compatibility | Grendel-type mags and bolt | Special mags and tapered bolt |
| Ballistics | Far superior | Limited accuracy and range |
| Suppressor Friendly | Very | Not ideal |
| Ammo Availability | Growing (premium) | Plentiful (budget)
|
For modern hunting and tactical applications, the Moriarti .338 ARC complete upper delivers more range, more stopping power, and better build compatibility.
Why Choose the .338 ARC from Moriarti Arms
Moriarti Arms offers a full selection of .338 ARC barrels, upper receivers, and bolt carrier groups, all designed to meet the needs of modern shooters. Every .338 ARC upper is built using our proven AR-15 platforms, ensuring smooth compatibility with Type II Grendel bolts and Grendel-pattern magazines.
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Each setup is tuned for suppressed or unsuppressed use, offering reliability and high-end performance whether you're on the range or in the field.
The Future of AR-15 Calibers
As ammunition technology continues to evolve, the .338 ARC stands out as one of the most versatile and powerful calibers available for the AR-15 platform. It bridges the gap between traditional intermediate rounds and large-caliber stopping power, all while maintaining a compact and lightweight rifle build.
Whether you're looking to upgrade from 5.56 NATO, 6.5 Grendel, or even 7.62x39, the .338 ARC offers a compelling balance of energy, suppression, and accuracy.
Ready to Build or Upgrade?
Explore Moriarti Arms’ growing lineup of .338 ARC upper receivers, barrels, and Grendel-compatible bolt groups designed specifically for AR-15 builds. As one of the first brands to bring this caliber to market, we’re committed to offering precision-machined components, fast shipping, and expert support.
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