After World War II rocked the globe, governments understood the need to maintain peace. One way in which they hoped to achieve this was with the formation of NATO.
At a very high level, NATO is an international alliance between many of the largest Western nations. The purpose was to prepare the West for threats to its integrity. In preparation for future wars, they created many standards, and one of these was the 5.56 NATO.
5.56 NATO is one of the most common types of ammo in semi-automatic rifles. It’s a versatile, high-pressure ammunition that sees usage in law enforcement and the military all over the globe. But it’s easy to confuse it with its sister ammunition: .223 ammo.
Keep reading as we discuss the difference between these two types of ammunition.
History of the 5.56 NATO Ammunition Standard
The 20th century was a whirlwind of technological advancement. In just 100 years, we went from horse-drawn wagons to men on the moon. Naturally, there was also a considerable amount of progress with weapons.
At the start of the century, machine guns were clunky, ineffective things. Then, in 1914, with the Great War, they became horrifically effective.
There was similar progress with semi-automatic rifles used by infantrymen on the front. Most of our men at arms were using bolt action rifles in the trenches. By the time World War II rolled around, a good percentage of those rifles were semi-automatic with larger calibers.
A problem quickly made itself manifest: there was a lack of standardization. New calibers were arriving on the market every year, as well as different weapon platforms. Soldiers storming the beaches of Normandy were using everything from the Thompson machine gun, to the BAR, to the M1 Garand.
Following the end of World War II, the nations realized that this lack of standardization was highly problematic. It would be far more effective for all soldiers to be using the same types of ammunition on the battlefield.
Creation of the 7.62 Standard
At first, they used the 7.62, a dense, recoil-heavy munition common to the Kalashnikov rifle. This round was thick, heavy, and able to puncture anything while doing incredible damage.
The issue with this ammunition was not its effectiveness. It was highly penetrative, able to pierce body armor and many layers of cover. You would not want to be on the receiving end of a soldier armed with a 7.62-chambered rifle.
Yet, this deadliness came at a cost. Soldiers quickly realized this round was too unwieldy and generally overpowered for their needs.
Recoil and muzzle rise was excessive when firing the 7.62. Just take an AK-47 down to your local shooting range and see for yourself. The weapon is a thing to be feared, but it kicks like a mule.
Plus, the rounds are much larger and a tad bit more difficult to reload. That tiny extra bit of weight adds up in the long run, too. Soldiers would often have to truck much heavier boxes of ammunition and be weighed down by heavier magazines.
Make no mistake, the 7.62 still sees use in military applications. You will find it often in the long-range marksman or sniper rifles with a bolt action. But a solution was needed for the average soldier, and thus the 5.56 came into existence.
Benefits of the 5.56 NATO
The 5.56 was trying to achieve several things at once. To be an effective, universal standard, to be deadly, but not excessive like the 7.62. The 5.56 does all of these things and more.
5.56 NATO excels in both close-range and long-range engagements. Soldiers can rest assured that the round will penetrate armor and thin cover sources.
Despite its deadly killing power, the 5.56 has the nickname “poodle shooter” because of how easy it is to fire. Muzzle rise is minimal. After a day at the range firing 5.56, your shoulder won’t ache in the same way as a 7.62.
Go out shooting at the range and see what we mean. When you fire the 5.56, the recoil is a light push. Yet the round will tear through any target you aim for.
Naturally, this means that soldiers retain much higher accuracy. Their equipment is much lighter–not just the magazine boxes, but the rifles as well. And since the ammo is universal across most US military rifles, soldiers can share ammunition among themselves.
Using the 5.56 for Civil Applications
Homeowners in search of defense solutions must be wary of the 7.62. It can easily pass through your house and the neighbor’s while still retaining enough velocity to kill. This makes it less than ideal for protecting yourself from a burglar if all you want to do is take down the burglar.
5.56 ensures homeowners have a weapon with the right punch, but not one that is overkill.
Law enforcement officers also benefit from a lighter, more effective round. A common issue that SWAT officers run into is keeping engagements tight, without introducing unnecessary collateral. The smaller 5.56 makes that reality more attainable.
All of that is great, but you may be wondering where the .223 comes into all of this. .223 ammo is very similar to 5.56, but there are some noticeable differences. Let’s discuss them.
.223 Ammo: How Does It Differ from 5.56 NATO?
If you have ever held a .223 and 5.56 in your hand, they look indistinguishable at first glance. They weigh practically the same, have practically the same shape, and would appear to fit in the same rifles. For the layman, the only obvious way to differentiate them is by the stamp on the rim.
Nevertheless, there is a difference between them, and it is one that you should know. Using 5.56 in a rifle designed for .223 won’t kill you, but it could damage you and/or your rifle. Here are the main differences between these types of ammunition.
5.56 Is Higher Pressure Than .223
The main difference between these two calibers is that 5.56 is high-pressure ammunition. The .223 clocks in at about 55,000 PSI, while the 5.56 is a much higher 58,000 PSI.
What does this have to do with you? The 5.56 has a much higher ammunition velocity. It punches through targets with more oompth than the .223.
Naturally, this means that a rifle must be tooled for 5.56. Higher pressure requires components that can contain that pressure and function after thousands of rounds. Everything from the ejection port to the firing pin must be able to handle a stronger kickback and higher temperatures.
If you use a 5.56 round in a rifle chambered for .223, the rounds could quickly damage or break the internal components. We do not recommend that you try this.
In some situations, you could suffer harm from the rifle if it bursts. This may not be similar to the result of spiked ammunition, but regardless, it puts you in danger.
Take the time to research whether your rifle can handle 5.56 before you use it. In many cases, rifles can handle both ammunition types with no trouble. However, just because it fits and it fires does not mean that it is OK.
5.56 Has Additional Room for Gunpowder
One tiny difference in the structure of the 5.56 is that it has a longer throat. You won’t notice this unless you put the 5.56 and .223 side by side.
A longer throat allows you to load an additional grain of gunpowder. This is part of the reason why the 5.56 is higher pressure. More gunpowder equals more boom, to put it crudely.
Less gunpowder means that the .223 has slightly different ballistics, especially for Rem ammunition.
Thicker Brass Components
To cope with the higher pressure, some 5.56 cartridges will be slightly thicker in certain places. This is to help contain the pressure and prevent splitting. It will not be perceptible from the outside without a set of calipers.
A similar situation is happening with the military’s new 6.8 mm ammunition. It has a much higher pressure, even compared to the 5.56 round. This necessitates a titanium base that is capable of withstanding the sharp kickback.
When Should You Use the 5.56, and When Should You Use the .223?
As you can see, there is not a world of difference between these two calibers. There is a reason why gun enthusiasts call them sister calibers. The differences are minimal, and in many cases won’t mean anything to the average gun owner.
Use 5.56 if you need more stopping power. Generally speaking, this round is more geared towards law enforcement and military purposes. It is quite rare that the average civilian actually needs it for home defense or target shooting.
Further, make sure that your rifle can handle 5.56. Check the manufacturer’s website and manuals if you’re not absolutely sure. Many manufacturers will make it clear whether the rifle can handle the 5.56 and .223 respectively.
But for the majority of civilian cases, the .223 is the round you should be working with. It serves well for general defensive purposes, as well as target shooting at the range.
Purchase All of Your Ammunition From Diamond K Brass
5.56 NATO is the gold standard of military ammunition, and for some civilian applications. It packs quite a punch despite being smaller than the previous 7.62 standard, in addition to being lighter and giving less recoil. However, 5.56 and .223 are not universally interchangeable.
Diamond K Brass is your source for certified once fired and bulk brass. Start with our primed brass to make your reloading experience much easier.
