Hornady’s .338 ARC Cartridge Designed For ‘Reliable Cycling With Both Supersonic And Subsonic Loads’

The new Hornady .338 ARC cartridge has a 2.260-inch maximum overall length to fit in AR-platform or micro-bolt-action rifles.

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posted on November 14, 2024
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338Arc Hornady 1
Hornady announces two initial loads for its new .338 ARC: one with a 307-grain Sub-X bullet in the company’s Subsonic line and a 175-grain hollow point bullet in the Black line.
Photo courtesy of Hornady

It was just a few years ago that Hornady released the 6 mm ARC (Advanced Rifle Cartridge), followed by the .22 ARC, both representing a quantum leap in what can be achieved, performance-wise, in AR-platform rifles. Now the company has announced .338 ARC, which the company bills as a cartridge that’s “purposely designed for hard-hitting subsonic performance.”

.338 ARC
Designed for solid subsonic performance, Hornady’s new .338 ARC cartridge delivers 1.5 times more energy than .300 Blackout Subsonic.

 

The new .338 ARC cartridge is an AR-platform-compatible caliber, similar to Hornady’s other offerings in the ARC cartridge lineup. Along with a smaller case designed by Hornady engineers for subsonic loads, .338 ARC sports a shoulder angle that’s optimized for subsonic loads. However, the .338 ARC is no slouch at supersonic velocities, either—it’s engineered for consistent pressure to provide reliable cycling with both supersonic and subsonic loads.

Available in Hornady’s Black and Subsonic product lines, initial .338 ARC offerings include a supersonic 175-grain hollow point bullet and subsonic 307-grain Sub-X bullet. Additionally, the twist rate is 1:8-inch.

.338 ARC bullets
The .338 ARC’s subsonic 307-grain bullet offering (left) and supersonic 175-grain hollow point bullet cartridge (right).

 

The real star of the show is the subsonic package with the 307-grain Sub-X bullet, which Hornady describes as the “most advanced performing subsonic bullet that we’ve ever made.” The heavy 307-grain Sub-X bullet provides increased terminal performance, with about 1½ times the energy of .300 Blackout.

As for the .338 ARC’s supersonic 175-grain hollow point load, it’s optimized for semi-automatic systems and will give a flatter trajectory. The 175-grain bullet is huge jump up from .300 Blackout supersonic loads, which generally are in the 100- to 110-grain range. Not only that, the .338 ARC 175-grain supersonic load should avoid issues like those found with .300 Blackout, where with some gun systems it can be difficult to get them to run subsonic and supersonic all on one gas setting.

Hornady says muzzle velocity from a 16-inch barrel for .338 ARC is 2,075 f.p.s for the 175-grain Black load, and 1,050 f.p.s. for the 307-grain Subsonic load.

.338 ARC headstamp
Ballistic coefficient for .338 ARC is .375 (G1) for the subsonic 307-grain bullet and .385 (G1) for the supersonic 175-grain bullet.

 

Besides the new .338 ARC cartridge, Hornady has announced new reloading gear for it, including cases, a cartridge gauge, full-length dies and seater dies, plus a die set. Plus, several companies have rifles and components available now or on the way soon. On the list are Aero Precision, AR Stoner, Ballistic Advantage, Black Rain Ordnance, Brownells, B&T USA, Carbon Six, CMMG, Faxon Firearms, Geissele, KAK Industry, Lantac-USA, Maxim Defense, Noveske, Odin Works, Palmetto State Armory, Preferred Barrels, Primary Weapon Systems, Proof Research, Satern Barrels, Seekins Precision, Stag Arms and Uintah Precision.

Both .338 ARC offerings can be found in 20-round boxes. Learn more at hornady.com.

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