Posted by Rob Orgel on 2024 Oct 17th
Hornady 338 ARC Versus 300 Blackout - Inside MDT
Hornady's ARC (Advanced Rifle Cartridge) lineup has quickly garnered attention for its impressive performance, with successful offerings like the 6mm ARC and 22 ARC. Now, Hornady introduces the 338 ARC, a round designed specifically with suppressed shooting in mind. But is it better than the popular .300 Blackout? Absolutely—and by a significant margin.
338 ARC VS 300 BLACKOUT
When it comes to subsonic ammunition, speed is a key factor. Most subsonic rounds are designed to stay below the speed of sound, typically around 1,100 feet per second (fps). Subsonic rounds are limited in speed to avoid the supersonic "crack," which can defeat the purpose of a suppressed firearm. Traditional subsonic rounds like the .300 Blackout top out at around 1,050 to 1,075 fps in their subsonic form, and while they work well, they are somewhat constrained in terms of power.
The .338 ARC takes a different approach. Instead of simply making a larger bullet in the same caliber (as in .300 Blackout), Hornady ups the ante by moving to a .338 caliber. This increase in diameter allows for a significantly heavier projectile without exceeding the speed of sound, thus offering a powerful subsonic round that can achieve more energy and penetration compared to a .30 caliber round.
338 ARC VS 8.6 BLACKOUT
One of the first comparisons made when discussing the 338 ARC is the 8.6 Blackout. The 8.6 Blackout was designed to offer even more power than the .300 Blackout while still being manageable in an AR-15 platform. However, the 8.6 Blackout requires an AR-10 platform due to its larger case size and overall power. While the 338 ARC may seem like a "little brother" to the 8.6 Blackout in terms of case size, it offers a compelling alternative for those who prefer an AR-15-sized platform. The 338 ARC provides similar ballistic performance to the 8.6 Blackout when used in subsonic configurations, but without the need for the bulk and weight of an AR-10. This makes it ideal for shooters looking for a suppressed, high-energy round in a more compact and maneuverable AR-15-style rifle. It gives users the best of both worlds: subsonic capability and the performance needed for a variety of applications, including mid-range hunting and tactical operations.
USING A 9MM SUPPRESSOR FOR 338 ARC
One of the concerns when dealing with larger calibers like .338 is the requirement for a specialized suppressor. Many shooters might assume that they'll need an expensive, heavy-duty .338 Lapua Magnum (LM) suppressor. However, the 338 ARC operates at relatively low pressures compared to other large-caliber rounds, making it compatible with suppressors designed for smaller calibers—such as 9mm suppressors. This opens up options for shooters who already own suppressors for other firearms, reducing the need for additional investments. Thanks to the lower pressure of the 338 ARC, you can use most 9mm suppressors with excellent results, making it a cost-effective choice for those building a suppressed AR-15.
Your 9mm suppressor will work just fine on a 338 ARC rifle. Photo courtesy of SilencerCo.
VERSATILITY AND USE CASE OF THE 338 ARC
The 338 ARC isn't just another "range toy." It is a versatile round that excels in various roles, from fun at the range to practical applications like short-range counter-sniper operations. With its low recoil and subsonic capabilities, the 338 ARC is an excellent choice for close-quarters engagements as well as for hunting mid-sized game within 200 to 250 yards. Whether you're targeting hogs, coyotes, or similar-sized animals, the 338 ARC provides a quiet, powerful solution for suppressed hunting.
In addition to hunting, the round could prove effective in law enforcement or military scenarios, particularly in tactical operations where the ability to remain discreet is paramount. The .338 ARC gives operators the option to engage targets at intermediate distances while keeping the noise down and the recoil manageable.
BUILDING A 338 ARC BOLT ACTION RIFLE
The 338 ARC is set to be available for purchase by the end of this year or early next year, and there are a few different options for how you can build your ideal rifle or pistol. Companies will likely offer complete rifles or pistols chambered in 338 ARC, and for the more hands-on shooter, barrels and other components will be available for custom builds. For those looking for a compact, high-energy firearm, a 338 ARC AR-15 pistol with a 6-inch barrel would be a great option. This setup would offer the maneuverability and suppressibility that suppressed shooting enthusiasts crave, while still packing a punch.
338 ARC ENERGY ON TARGET
One of the standout features of the 338 ARC is its impressive energy delivery, especially within shorter distances. In fact, within 100 yards, the 338 ARC provides ballistics that are very close to a .44 Magnum, a renowned powerhouse for close-range shooting and hunting. This makes the 338 ARC an excellent choice for suppressed hunting or tactical use in environments where subsonic rounds are preferred but high energy is still needed for reliable target impact. The larger projectile of the 338 ARC, combined with its subsonic nature, ensures that it delivers substantial energy to the target without the sonic crack of supersonic rounds, making it a quiet and effective option for close-range engagements. Whether for hunting medium-sized game or tactical applications, the energy of the 338 ARC within 100 yards rivals that of some of the most respected handgun cartridges, making it an ideal round for discreet, powerful shooting in close quarters.
338 ARC would be perfect if you want to hunt with an AR15 patterned rifle. Photos courtesy of Anthony Amantine.
RATE OF TWIST: CRITICAL CONSIDERATIONS
When building a 338 ARC rifle, it's essential to pay attention to the barrel's rate of twist. The most common twist rate for the 338 ARC is 1:8, opposed to the twist rate commonly used for the 8.6 Blackout and 338 Spectre of 1:3. However, shooters should exercise caution with such a fast twist rate, as it can lead to problems if the bullet isn't properly stabilized.
Now we can remove the some problems, particularly one as fast as 1:3, can result in excessive pressure on the round, potentially causing it to come apart inside the barrel or immediately after leaving the muzzle. This can lead to catastrophic failures, including damage to the firearm and suppressor. It's critical to ensure that the ammunition you're using is properly suited to your barrel's twist rate to avoid these issues. Always consult the manufacturer's guidelines and choose the right ammo for your build.
CLOSING THOUGHTS
The 338 ARC is poised to be a standout round for suppressed shooting enthusiasts. With its larger diameter, increased power, and compatibility with AR-15-sized platforms, it offers a compelling alternative to the .300 Blackout and even the 8.6 Blackout for those who prefer lighter, more compact firearms. Whether you're looking to build a new rifle or pistol, or simply upgrade your existing setup, the 338 ARC promises to deliver exceptional performance, low recoil, and a fun, versatile shooting experience. Keep an eye out for its release—this round is set to make waves in the shooting world.
CALIBER RESOURCES FROM MDT
- Copper VS Lead - Meateater & Modern Day Sniper
- Analysis: 6.5 PRC
- Analysis: 6.5x47 and 6x47 Lapua
- The Carbon Ring
- Analysis: .277 Sig Fury - Inside MDT
- Is the 308 Winchester Still Relevant?
- Analysis: 6.5 Creedmoor
- Why All The Hate For The 30-06
- Loading 6MM ARC And .223 REMINGTON with A Dillon Progressive Press
- Hornady 6MM ARC For Competition
- Analysis: 6MM BR NORMA
- Fire Forming and Loading 223 AI
- Loading 6GT with Hodgdon H4350
- 270 Winchester and Colorado Elk
- 6mm GT Load Development
- Capable And Versatile: A Close Look at the 6.5X55 Swedish
- Analysis: .338 Lapua Magnum
- Analysis: 7MM PRC
- 280 AI: Merging Power and Precision
- 338 Lapua: A Journey
- Analysis: 8.6 Blackout
ABOUT THE AUTHOR
Rob Orgel enlisted in the USMC in 2004 as an Infantry Rifleman (0311), serving with 3rd Bn 1st Marines in Iraq, including roles as a point man in OIF-3 & team leader in OIF-6. Later, he joined the 1st Marine Regiment, achieved the rank of Sergeant in 2010, & continued service in Afghanistan. Upon returning, he became a Combat Instructor at the School Of Infantry West. Transitioning to private military contracting with Securing Our Country (SOC), he instructed at the American Embassy in Iraq. In 2018, Rob became Chief Instructor at GPS Defense Sniper School, revamping their program. Now, as owner & lead instructor at Emergency Response Tactical, he focuses on training novice to advanced shooters on the range over 300 days a year.