Caliber Crackdown: 223 Remington vs 5.56 NATO

If you’re a gun owner passionate about target shooting and hunting, chances are you have a rifle chambered to shoot 223 Remington or 5.56x45mm NATO. For those considering but have yet to purchase, you might ask yourself, “Which is the better cartridge?” In this blog, we will explore each cartridge's history, similarities, and differences. 

Understanding the Basics of the 223 Remington vs 5.56 NATO 

In the ammunition world, 223 Remington and 5.56 NATO are two of the most abundant centerfire cartridges on the market. Both 5.56 and 223 ammo can be cost-effective when purchased in bulk and can be used in various applications, including hunting, target shooting, personal defense, or competition. You’ll find all sorts of carbines, semiautomatic rifles, and bolt-action rifles for each cartridge. Even though they are not 100% interchangeable, their blood runs with similar DNA.  

The 223 Remington was developed and manufactured in the late 1950s to create a high-velocity small-caliber cartridge for the army. It quickly became a household name and the go-to ammo for everyday riflemen, both military personnel and consumers.  

As time passed, technology advanced, and the ammo market also expanded. Developed and manufactured in the 1970s, the 5.56 was created from its parent cartridge, the 223 Remington! This cartridge was designed to rival the larger and heavier European 7.62×51mm, and is chambered by the US Army’s renowned M16 Rifle. The 5.56 is essentially a souped-up version of the 223 Remington.  

Differences between 223 and 5.56? 

The differences are simple. First and foremost, 223 Remington is loaded to SAMMI Specs while the 5.56 is loaded to NATO specs. Second, the 5.56 is loaded at higher pressures than the 223. Third, the 5.56 has a longer chamber length in the firearm.  

The average pressure of a loaded 223 falls within 52,000 – 55,000 PSI, while the 5.56 falls between 55,000 PSI and 62,000 PSI. The difference in pressure yields higher velocities for the 5.56, making it the hotter load of the two. Additionally, the higher pressure calls for a longer chamber length for the 5.56, which extends the effective range a tad when comparing the same bullet.    

223 vs 5.56 for Hunting: Choosing the Right Cartridge 

Through correct bullet selection, the 223 or 5.56 can be an effective hunting cartridge for varmints and medium-sized big game, such as deer. Just be sure to check your state regulations about using these cartridges before pursuing deer. Remington loads SAMMI cartridges. Remington does not load NATO cartridges such as the 5.56 NATO. However, Remington does provide 223 shooters with an appropriate 223 load for hunting scenarios. Remington’s iconic Core-Lokt product family offers a Core-Lokt loaded with a bonded 62-grain bullet. This load can easily tackle small and deer-sized game with proper shot placement. 

Both cartridges are great options for varmint/predator hunting. Pairing these cartridges with a scoped rifle can provide superb long-range accuracy. If you are looking for a bolt-action rifle, consider the 223. More bolt-action rifles are chambered for the 223 than the 5.56. Additionally, due to the higher pressures, the 5.56 may maintain better terminal performance velocities at further ranges compared to the 223.   

223 vs 5.56 for Home Defense and Tactical Applications 

Much like a hunting scenario, having a round loaded with a bonded bullet is best suited for scenarios where penetration is essential. However, if you're hitting the range or training for defense scenarios, all you’ll need to have loaded is a full metal jacket bullet (FMJ). The same goes for any range applications you encounter. For both 223 and 5.56, you only need an FMJ for target shooting. This saves you dollars over the long term.  

Competitive Shooting 

A popular competition event for 223 and 5.56 is 3-Gun. 3-Gun is a timed competition in which participants shoot pistols, rifles, and shotguns through an action-packed three-stage course. The shooter who evades the “no shoot” targets and hits the most targets fastest wins. Both 223 and 5.56 will provide the shooter with an AR-style firearm base that is easily accessorized and is agile enough to perform efficiently in 3-Gun. When the stakes are high and time is your enemy, consider Remington's Premier Match ammo for 223 Remington. Premier Match is Remington’s top-shelf 223 target ammo. Loaded specifically with match-grade bullets and premier components, this load will deliver tournament-winning results up close and at ranges.  

Cost and Ammo Availability 

The cost of both cartridges depends on your intended use. For a day at the range, lower-priced FMJs will suit your needs. On the other hand, the bonded bullets used for defense or hunting applications will be slightly above the cost of FMJs.  

Looking to save some money? Consider buying bulk 223 ammo or bulk 5.56 ammo. Although the initial cost may be higher, shooting all the rounds purchased in bulk will be less than the same number of rounds fired through multiple boxes.  

As we’ve discussed, ammo for both 223 and 5.56 is very accessible. You can find either of these cartridges at a local retailer. Looking for something specific? Browse Remington’s 223 ammo page, and we’ll ship the product straight to your door.  

FAQs 

Can I shoot 223 rounds through a 5.56 firearm? 

• Yes. Since the chamber pressures are lower than the rating on the 5.56 firearm, you can shoot a 223 round through a 5.56 firearm. Always read your owner’s manual.  

Can I shoot 5.56 rounds through a 223 firearm? 

• No. You cannot shoot 5.56 through a 223 firearm. Since the 5.56 cartridge is loaded at higher pressures, discharging a 5.56 in a lower-rated firearm can be dangerous. Always read your owner’s manual.  

What is the difference in recoil? 

• Both 223 Remington and 5.56 NATO have light recoil. Between the two, there is no significant difference.  

Are there legal restrictions or requirements for owning 556 ammo? 

• The only legal restriction is being of age in the United States. The age to purchase centerfire rifle ammo in the United States is 18 years of age. Just because 5.56 is not a SAMMI cartridge does not mean it is unavailable to purchase.  

Comparing apples to apples, the 223 and 5.56 perform similarly in most scenarios and platforms. There is no wrong answer. Still on the fence about which one to choose? Head to the range and give both a try!