5 Best Intermediate Calibers: The Best of Both Worlds

The intermediate rifle cartridge completely changed the world of rifles. It was a revolutionary idea that introduced a new type of fighting rifle, a new type of patrol rifle, a new type of home defense rifle, and even a new hunting rifle.

Intermediate rounds are often considered Goldilocks’ choice of rifle rounds. It’s not too big or small and is just right for me in so many ways.

The term intermediate cartridge isn’t one we use too often, and it’s mostly one you are from military history nerds, reloaders, and guys really into the art of the rifle.

Let’s discuss the intermediate cartridge, its history, and its benefits before talking about a few of the more popular intermediate cartridges and what they’re good for.

What is an Intermediate Cartridge?

The general definition accepted is a rifle or carbine cartridge that falls somewhere between a pistol cartridge and a full-powered rifle round.

That technically encompasses cartridges like 5.7x28mm and 4.6x30mm, which fit the definition but don’t perform the way a real intermediate cartridge does.

Intermediate rounds typically have an effective range of 300 to 500 yards in a standard rifle. They have short cases, typically not exceeding 45mm in length. They are widely used by militaries, police forces, and civilians worldwide.

It’s arguable who did it first, and a lot of credit goes to Nazi Germany with the StG 44 and its 7.92 Kurz round. The 7.92 Kurz and StG 44 was undoubtedly the first successful combination of an assault rifle and a military-issued intermediate cartridge. But neither was the true first.

In 1917, the Americans had the experimental Winchester Burton Machine Rifle, and the French had the Ribeyrolles 1918 automatic carbine with its 8x33m cartridge. Both were ahead of their time but remained experimental.

Winchester created the .351 Winchester Self-Loading cartridge in 1906, which is arguably an early intermediate cartridge. The follow-up to the .351, the .345, is almost certainly the first real intermediate cartridge.

In a post-World War 2 world, the Soviets were the first major power to adopt an intermediate cartridge and field force-wide. The 7.62x39mm used in the SKS and AKM series rifles was hugely successful.

The British had long considered the intermediate cartridge and experimented with calibers like the .280 British and the 4.85x49mm but were beholden to NATO standardization.

The United States heavily influenced NATO to adopt the 7.62x51mm NATO cartridge, making it a reality. They effectively pushed the British away from intermediate cartridges and saddled them with a full-power rifle round for the FN FAL.

However, less than 2 decades later, the United States changed its mind and adopted the 5.56x45mm round. The American adoption of 5.56 led to the rest of the world following suit.

This effectively split the globe, with the Western countries using 5.56x45mm and many Eastern countries adopting 7.62x39mm.

Since then, other intermediate calibers have entered the fray, including the Russian 5.45x39mm, the Chinese 5.8x42mm, and many more.

What Makes These Rounds Successful?

The intermediate cartridge offers the average shooter exactly what most people need. They are rounds that are capable of going out to 300 to 500 yards with decent accuracy.

Most of us will never shoot at 500 yards, so spending the money for an expensive full-powered rifle doesn’t make much sense.

Due to the overwhelming popularity of guns like the AR-15 and AK-47, intermediate rifle ammo tends to be more common and more affordable.

The ammo itself also tends to be lightweight. This makes it much easier to carry more ammo in a loadout. Carrying 210 rounds of 5.56 isn’t tough, but 210 rounds of 7.62 NATO gets heavy awfully quick.

Lighter ammo also equals lighter recoil. The guns beat you up less, and you can shoot all day without getting exhausted. Low recoil also makes follow-up shots more manageable and often increases combat accuracy.

Another often understated benefit to these light recoiling rifles is safety. These are rarely, if ever, guns an adult shooter cannot safely handle.

The Best Intermediate Cartridges

We have tons of intermediate-caliber options these days. Some are more common than others, but they are all fairly easy to handle and available on several different platforms. While most rifles chambering these cartridges are semi-auto, there are several single-shot, lever, and bolt action rifles available that chamber several intermediate cartridges.

Let’s look at the five best intermediate cartridges currently on the market and talk about the unique benefits each offers.

1. 5.56x45mm/.223 Remington – Do It All Cartridge

The 5.56x45mm and .223 Remington are two sides of the same coin. The two have minor differences, but if your rifle can chamber 5.56, it can shoot .223 Remington. If the rifle says .223 Remington only, following those directions is best.

These are the most common intermediate cartridges in the United States. Finding ammo, rifles, magazines, and even specialty optics built around these guns is super easy. It’s everywhere, and its popularity has created this massive market and turned the 5.56 into a jack of all trades.

The cartridge tends to over-penetrate drywall less than shotguns and handguns for home defense. Barrels can be as short as 10.3 inches and deliver favorable results with the right ammo. This is the primary cartridge of the AR-15, which makes it one of the most common cartridges on the market.

Hunters can use the 5.56 or dedicated .223 rounds to hunt everything from prairie dogs to deer. It’s an excellent varmint and predator cartridge. Guns chambered in these rounds are usually lightweight, allowing for quick and easy shots on target.

In sports like 3-Gun, the 5.56 dominates. It’s cheap enough to shoot in bulk and accurate enough to compete, making it a go-to cartridge. If you want one intermediate cartridge to be pretty good at everything, then the 5.56/.223 is the way to go.

2. .300 Blackout – Short and Suppressed

Over the years, there have been a ton of new rounds that claim they will be the ones to knock the 5.56 from its top spot; none have succeeded. But the .300 Blackout takes a different route.

It was never meant to replace the 5.56 but to complement it. Instead, it was intended to address the areas where the 5.56 was weak while taking very little effort to convert existing 5.56 guns. It uses the same mags, bolt, upper, lower, etc. All you need to do is swap the barrel and gas system.

The .300 Blackout is perfect for a super short, PDW-sized AR-15. AAC designed the .300 Blackout cartridge to be used in a platform that’s basically the same size as a submachine gun.

Another huge benefit of using a .30 caliber cartridge is the ability to run heavy projectiles, which can be subsonic. The heavy subsonic projectiles have a limited range but are extremely easy to suppress.

Users can still instantly swap to supersonics to get that range back at the cost of less efficient sound suppression.

If the 5.56 is the King of the AR market, the .300 Blackout is the crown prince. It isn’t quite as affordable as 5.56, but it is still reasonably priced and has been widely accepted by the market.

It’s also an excellent cartridge for home defense, especially in a short and suppressed platform. In states that ban hunting with any projectile smaller than 6mm, it’s also a viable alternative.

The .300 Blackout delivers a little more recoil than 5.56 but still provides a super controllable and easy-to-use intermediate rifle round.

Be sure to check out our article on the Best .300 Blackout AR Pistols & Rifles!

3. 7.62x39mm – Close-Range Power

The 7.62x39mm has been going strong since 1947. This small .30 caliber round has found success across various platforms. This includes the famed AK-series but also the AR-15, the Ruger Mini Thirty, the SKS, and various bolt-action and single-shot rifles.

It offers a lot of energy transfer for an intermediate rifle round, which makes it a great penetrator that can slug its way through most forms of cover. For hunting, the round does a solid job at moderate ranges.

With a standard 123-grain projectile, shooters are getting 1,607 ft-lbs of energy. It’s quite potent, and for comparison, a 125-grain 300 Blackout is giving you 1,360 ft-lbs. It’s a hard-hitting cartridge that does well up close.

For home defense, it has a lot of overpenetration potential, and I wouldn’t choose it on that factor alone.

The max effective range is about 300 yards, but realistically, anything past 200 yards and you start to see some significant drop.

There is a bit more recoil with 7.62x39mm than most other intermediate cartridges. It’s not a bruiser, but the guns buck a bit more. Recoil and muzzle rise tend to be less controllable than 5.56 or .300 BLK.

While 7.62x39mm used to be a lot cheaper, these days, it’s roughly the same price as 5.56 cartridges. Despite this, it’s still fun to shoot. If you’re an AK fan, you have caliber options these days, but the classic 7.62x39mm round is still the way to go.

You can take a look at our dedicated article on the Best Ammo for the AK-47!

4. 6mm ARC – Long-Range Precision

Cartridges within the 6mm to 6.5mm range tend to have excellent ballistic properties. Several intermediate cartridges utilize the ballistic superiority of 6mm rounds.

The 6mm ARC (Advanced Rifle Cartridge) is one of the latest entries into that category, but it is also the one with the most potential.

The 6.5 Grendel and 6.8 SPC cartridges are great, but the 6mm ARC has proven to be the most capable and dynamic option. It allows you to reach out and touch targets beyond the normal 500-yard range — all the way up to 1,000 yards, in fact.

And by reach, we mean it can remain supersonic out to 1,000 yards. You are still looking at a decent amount of drop at that distance, but the cartridge can still make the stretch. Excellent ballistics make it one of the best long-range intermediate cartridges on the market.

The 6mm ARC gives you the range of a full-powered rifle with intermediate caliber size and recoil. It hits a higher level of recoil than standard 5.56, but not that much more. It’s quite loud, but the recoil and muzzle rise are easily controllable.

It’s worth noting that the 6mm ARC has a SAAMI load set that allows the cartridge to operate safely in gas-operated guns like the AR-15. A second set of load data amplifies the max pressure for intended use in bolt-action rifles.

While the 6mm ARC has impressive performance, it suffers from being so new. Magazines, barrels, guns, and more aren’t as common as other cartridges, and the ammo is also pricier and tougher to find.

5. .350 Legend – The Hunter

Last but not least, if you want an intermediate hunting cartridge, the .350 Legend may be for you!

Any of the intermediate cartridges on this list could be used for hunting. But if you pursue white-tail deer, hogs, and some varmints, the .350 Legend can be a much more versatile hunting cartridge than any of the above.

It can take deer, hogs, and coyotes, but with the right load selection, it can even take bears. The cartridge meets seemingly all requirements for ethical hunting and all legal requirements across the United States.

The .350 Legend was developed for states that only allow straight-walled cartridges for hunting. Winchester developed the cartridge to work in AR-type rifles, and it shares many similarities with the .223 Remington as a result. They are the same overall length and have the same rim diameter.

It’s a clever idea that instantly opened up a large market for the cartridge. You can convert a standard multi-cal AR to .350 Legend simply by swapping uppers.

The .350 Legend has really taken off, and there are tons of options, including hollow points, bonded ammo, and more.

Compared to 5.56, .350 Legend has a nice stiff recoil impulse, but it’s still not painful. The round does have a fairly short effective range, out to about 250 yards max. For most hunters, that is more than enough. The ammo isn’t super cheap, but the uppers, barrels, guns, and mags are becoming common and affordable.

Why You Should Trust Us

Pew Pew Tactical author Travis Pike spearheaded this article. Travis spent a lifetime shooting as a kid and later joined the United States Marine Corps, where he spent five years as an infantryman. Travis is also an NRA-certified instructor and Concealed Carry Instructor for the state of Florida. He has tested a large number of different guns, gear, and cartridges and has thousands of articles to his name with a variety of publications, including Pew Pew Tactical.

This review was edited by Pew Pew Tactical Editor Wyatt Sloan. Wyatt is an NRA and USCCA-certified instructor with previous experience as a competitive shooter. He personally owns over 200 firearms in over 50 different chamberings and has 10 years of home-based FFL firearm sales. Wyatt uses his extensive experience with firearms at large to test guns for Pew Pew Tactical — evaluating them based on our standards and metrics.

Editor-in-Chief Jacki Billings runs our experienced team of reviewers and edited this review. She is an NRA-certified Basic Pistol Instructor as well as a member of the Society of Professional Journalists, ACES: Society for Editing, and the Professional Outdoor Media Association. Jacki has a bachelor’s degree in journalism and has worked as a media professional for close to 20 years, specializing in gun media for almost 10 years. With 2,000+ articles to her name, she uses her professional journalism and editing experience to set testing protocols and editorial standards for Pew Pew Tactical.

Final Thoughts

Intermediate cartridges will likely continue to dominate the rifle market for the time being. While the Army’s experiment with the .277 Fury is interesting, I’m betting it’ll be M14 round two.

It is just too hard to beat a light-recoiling, easy-to-control, and accurate cartridge available in lightweight and compact platforms.

What are your thoughts on intermediate cartridges? Do you have a favorite? Let us know in the comments below! Looking to reach out further? Check out our article on Long Range Shooting – Intro & Fundamentals!