Reloading the ARCs

Interested in reloading for the ARC family of cartridges? We pulled together a host of data for 6mm ARC, 22 ARC, and 338 ARC including powder selection, bullet grain weights, and performance potential. Watch the video and read on to learn everything you need to load these specific cartridges.

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Overview of the ARCs

The ARC family – Advanced Rifle Cartridge – started with the 6mm ARC and expanded to the 22 ARC and 338 ARC. All ARC cartridges are based off the 6.5 Grendel with a 2.260” cartridge overall length and 7.62x39mm case rim.

Though all three cartridges are designed for the AR platform, I’ve built 6mm ARC and 22 ARC bolt action rifles that had stellar long range results.

The 6mm ARC was designed for the AR-15 with a 2.260” cartridge overall length. It was introduced by Hornady in 2020 and based on the 6.5 Grendel (7.62x39mm case rim) but has greater velocity and less recoil than its parent.

It is optimized for long-range applications and defense with long, high BC 103 to 108-grain 6mm projectiles.

The 22 ARC is extremely pleasant to shoot, shares the 2.260” COL and case rim, and is designed for long range hunting and varminting.

It offers very mild recoil and accepts a host of .22 caliber projectiles, the best range being 62-grain to 88-grain bullets.

Hornady released this cartridge in 2024.

Released in 2025 by Hornady, the 338 ARC deviates from the other ARCs in that it was purposefully designed for subsonic performance.

Gavin shooting the ODIN Works 338 ARC out to 200 yards

Though part of the ARC family, it has more in common with the 300 AAC Blackout, doing best with hard-hitting, heavy bullets weighing between 175 and 307 grains.

Loading Considerations

Loading for the ARC family requires most of the same tools as reloading for other bottleneck rifle cartridges. Single-stage, turret, or progressive presses need to have 2.260” capacity and all three ARC calibers take the same shell holder/shellplate.

The dies are caliber-specific and crimping is encouraged for reliable feeding through ARs. Top-heavy cartridges like the 338 ARC tend to struggle with bullet feeders, so pay extra attention.

If you plan to shoot semi-automatic, be sure to test the first rounds for proper cycling before loading in mass quantities.

As always, a progressive press is best suited for high-volume, while a single-stage or turret press is preferable for precision applications.

Loading Data

DISCLAIMER: Data shown is for reference only, use at your own risk. The latest data is available from Hodgdon in their Reloading Data Center.

It is important to remember to NEVER start with a maximum load—you should always work your way up to it. I have previously done other load development and am showing maximum loads in this video, only to show the capabilities of each cartridge. Keep in mind that when selecting an optimal powder you want to be in the range of case utilization where the load begins to become compressed when the bullet is seated.

In reviewing powder choices for all three ARC calibers, it was immediately obvious that the 338 ARC took faster powders than the 22 ARC and 6 ARC, which had zero overlap with the rest of the family. In contrast, there are a number of powders suitable for both 22 ARC and 6 ARC.

22 ARC

I referenced the latest data from Hodgdon in updating my powder burn rate charts, organized in order from fastest to slowest and color-coded by bullet weight range. Faster powders from Ramshot X-Terminator to Accurate 4064 are limited to light bullets only while most powders from Accurate 2520 to StaBALL 6.5 work for all appropriate bullets. Per the chart, no powders are exclusive to heavy bullets.

I also pulled maximum load data for the lightest and heaviest weight bullets to get a better idea of the full range of performance potential. The 95 grain bullet max loads close in on standard 6.5 Creedmoor velocities.

I really enjoy shooting the gentle 22 ARC, which falls somewhere between rimfire and traditional centerfire shooting scenarios. It also is a great caliber to watch trace and see your hits on target!

6mm ARC

The 6mm ARC has a similar burn rate range to the 22 ARC, but with less distinctive lines between ideal powders for heavy and light bullets.

Selecting 58 grain and 110 grain bullets for comparison, max loads with the lighter bullets run approximately 3,400 fps and close to 2,550 fps with the heavier bullets.

A lightweight 6mm bullets at these velocities will have explosive performance on varmints, matching 22 ARC.

338 ARC

Once again contrasting 22 ARC and 6 ARC, the 338 ARC has a very compact range of ideal powders, with no powders specific to light bullets.

Many of these powders match the ideal powders for 300 AAC Blackout. The heavy bullets are ideal for subsonic applications. (Pro Tip: Hodgdon has a specific section for Subsonic reloading data on their website!)

I haven’t loaded for 338 ARC yet, but am looking forward to doing so and toying with the idea of a unique bolt action build.

As expected, maximum loads for 160-grain bullets vs. 300-grain bullets show a distinction between subsonic and supersonic.

Conclusion

Wrapping it all up, there are a variety of powder options for all ARC cartridges, but 22 ARC and 6mm ARC share more aspects of ballistics and reloading than 338 ARC. They also both work great in bolt action! All three ARCs share the same COL and case rim diameter though with different applications.