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.

by
posted on November 14, 2024
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
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.

Latest

2026 ARC Scopemounting 6
2026 ARC Scopemounting 6

NRA America’s Rifle Challenge: Kyle Lamb’s Guide to Mounting a Scope for ARC

Kyle Lamb walks through optics mounting with practical advice on leveling, eye relief and preventing scope shift during ARC competition.

Politics, Weather and Rising Stars Mark a Turning Point: 1990 National Matches

The 1990 National Matches at Camp Perry saw funding threats, severe weather cancellations and major victories by shooters like David Tubb and Jim Meredith as a new decade began.

Review: GP Arms Patriot Rebel

The GP Arms Patriot Rebel is a mid-level 2011 built for Limited Optics, delivering 1,000-plus rounds of flawless reliability including a full USPSA Nationals.

Milan Cortina 2026: Team USA’s Masters Defends Paralympic Biathlon Title With Perfect Shooting

Oksana Masters defended her Paralympic biathlon sprint title with flawless shooting at Milan Cortina 2026, with teammate Kendall Gretsch taking silver.

MidwayUSA Foundation Sends $7.5 Million to 995 Youth Shooting Teams Across 46 States

MidwayUSA Foundation concludes its February grant cycle with more than $7.5 million paid to youth shooting teams nationwide, funded by endowments that allow teams to draw 5% annually in perpetuity.

2026 NSCA Championship Tour Opens in March With Eight Stops and Expanded Winchester Ladies Cup

The NSCA Championship Tour, Powered by Winchester returns for 2026 with eight stops, $40,000 in added Ladies Cup payouts and 120 cases of ammunition for women competitors.

Interests



Get the best of Shooting Sports USA delivered to your inbox.