.223 Wylde has seen a recent explosion in popularity among AR aficionados, who claim that it offers shooters superior accuracy, greater versatility, and more reliability. But what is .223 Wylde, and how much of the hype is justified? We’re taking an in-depth look at the history, development, and benefits of the .223 Wylde chamber design, and seeing how it stacks up against the classic .223 Remington and 5.56 NATO designs.
What is .223 Wylde?
Cartridge or Caliber?
First, let’s clear up a common misconception: .223 Wylde isn’t a cartridge, and if you go to your local shop and ask for a box of it, the only thing you’re going to get is a funny look. That’s because it’s actually a hybrid chamber designed to safely and accurately fire both .223 Remington and 5.56 NATO cartridges with equal ease, and setting up an AR-15 in .223 Wylde is as simple as swapping out a barrel or buying a complete upper.
To understand why .223 Wylde was developed in the first place, we need to take a brief historical detour back to 1957, when the .22 caliber rifle cartridges were being tested for military use. That year, Remington Arms teamed up with Fairchild Industries to create the Remington .222 Special for the U.S. Army. To avoid confusion with civilian .222 cartridges that were also being developed at the time, the cartridge was renamed to .223 Remington, and was formally adopted by the Army as their new intermediate cartridge in 1962.
However, a decade later, the Belgian firearms manufacturer Fabrique Nationale was tasked with developing a standard round for NATO use based on the .223 Remington cartridge that the United States had already heavily invested in. FN’s solution was the 5.56x45mm NATO round, which shared the same exterior dimensions with .223 Remington but, according to FN’s testing, boasted a better drag coefficient as well as a marginally higher muzzle velocity and effective range thanks to differences in powder load and chamber leade, in exchange for creating higher pressure inside the chamber when fired.
In practical terms, the result was that a rifle chambered in 5.56 NATO could safely fire .223 Remington (at the cost of slightly reduced accuracy), while a rifle chambered in .223 was not rated for the increased pressure created by the 5.56 cartridge. The minor loss of accuracy when firing .223 out of a rifle chambered in 5.56 was considered a non-issue for a semi-automatic rifle designed for military use, and so over time the majority of rifle manufacturers began chambering exclusively in 5.56 NATO.
Problem solved, right? As it turns out, not quite.
Bill Wylde, a gunsmith from Greenup, Illinois who specialized in precision rifles, compared both cartridges and realized that because they shared identical case dimensions, specifications from both chamberings could be combined in order to achieve the best of both worlds. As to how this was accomplished, let’s look at a detailed comparison between these different chambers.
.223 Remington vs. 5.56 NATO vs. 223 Wylde
As we’ve established, the exterior dimensions of the .223 Remington and 5.56 NATO cartridges are identical. So why aren’t they completely interchangeable? The answer comes down to chamber design.
The dimensions of a .223 chamber are slightly smaller in general, but the real issue lies in the leade – the area between the front of the chamber and the point where the bullet connects with the rifling of the barrel.
In comparison, the 5.56 NATO chamber is slightly roomier, with a longer leade and tighter leade angle to accommodate longer bullets and the higher pressure of the 5.56 NATO cartridge.
Because the 5.56 chamber is built to withstand higher pressures, shooting the lower-pressured .223 Remington cartridge out of it is no problem at all. But when shooting 5.56 NATO out of a .223 chamber, the shorter leade combined with the extra grain of powder in the cartridge creates a significant pressure spike, which can theoretically lead to a catastrophic failure that could destroy the firearm and injure the shooter.
Realistically, the odds of that happening are slim, and the most likely issues you will run into from shooting 5.56 ammo out of a .223 chamber are increased fouling, split casings, and blown primers, all of which are reason enough to avoid doing it. When it comes to putting your face near a hunk of metal that is constantly containing small explosions, it’s probably not a good idea to roll the dice.
But if a 5.56 chamber can handle .223 without any problems, why the need for the .223 Wylde? Rather than a question of safety, it comes down to performance.
Even though the 5.56 NATO chamber will reliably feed .223 ammo, there are still some minor compromises being made. First of all, because the dimensions of the 5.56 freebore – the length and diameter of the leade – are slightly larger when compared to a .223 chamber, a .223 round sits a bit looser in a 5.56 chamber, which theoretically results in a minor loss of accuracy and muzzle velocity – though probably not enough to make a difference for the casual shooter, especially with high-quality modern ammunition.
The other consideration is twist rate: though NATO specs demand a 1:7 twist in their rifles so that standard ball ammunition and tracer rounds can both be stabilized out of the same barrel, the majority of civilian rifles on the market have a 1:9 twist rate, which is ideal for 55gr and 62gr ammo. Where the .223 Wylde chamber excels is sheer versatility – a .223 Wylde barrel with 1:8 twist not only handles standard factory loads with ease, it’s also great at slinging the longer, heavier bullets that see common use in long-distance shooting competitions. In fact, it handles the 80gr ammo used by most Sport Rifle Competitions so well that .223 Wylde has become the chambering of choice for manufacturers of National Match-configuration AR-15s.
To sum it up, by combining the leade angle of the 5.56 NATO chamber and the tighter .2240 inch freebore of the .223 Remington chamber, the .223 Wylde chamber is able to handle a wider variety of ammunition without any concerns about over-pressurization or any loss of accuracy or muzzle velocity stemming from a wider freebore.
.223 Wylde Pros and Cons
.223 Wylde is the best of both worlds. One is cautioned not to shoot military 5.56 ammo in a .223 chamber due to the military round’s increased pressure that it’s loaded to – 55,000 psi vs 62,000 psi. On the other hand, .223 ammo shot in a 5.56mm-chambered rifle may not exhibit the best accuracy it’s capable of, due to the way the military chamber is cut.
The major difference between .223 and 5.56 chambers is the longer and larger-diameter freebore that the 5.56mm exhibits. That distance is .059” vs. .025” for the .223 chamber. It also is a bit larger, at a .226” diameter vs. the .223’s .224”. The slightly larger dimensions allow rifles and machine guns to function even when they are dirty or otherwise fouled.
Bill Wylde’s solution was to cut his chamber with an even longer freebore length of .078”. This allows longer and heavier bullets to be used, with no decrease in accuracy.
So… to address the topic of pros and cons… I’m not sure there are any cons. Maybe, just maybe, you’ll have a load that performs better in an actual 5.56mm-chambered rifle than it does in a Wylde chamber, but that is doubtful given what I hear and read about Mr. Wylde’s solution.
It does tend to handle 80-grain match bullets better… as a matter of fact, rifle manufacturers who make National Match barrels chamber them in .223 Wylde. It tends to shoot both .223 and 5.56mm ammo very well, and as I just mentioned, longer/heavier bullets are a dream to shoot.
So… I only see “pros”. It seems that most .223/5.56mm AR shooters are “wild about the Wylde”!
Should You Switch to .223 Wylde?
When .223 Wylde first hit the scene, the question of whether it was worth the money to upgrade was a bit more difficult. It took a while for the chambering to gain widespread popularity, and buying a 223 Wylde upper or barrel usually meant spending a decent chunk of extra cash that was hard to justify for a casual shooter who only spent time at the range plinking with factory loads.
Nowadays, that gap has mostly disappeared – whether you’re buying an assembled rifle, a complete upper, or just a barrel, there’s little to no difference in cost to go with the .223 Wylde chamber instead. If you’re at all interested in getting into long-range target shooting or competitive shooting with your AR-15, or want to hunt with heavier bullets that can punch through brush and more reliably harvest game like hogs and whitetail, switching to .223 Wylde is a no-brainer – there’s a reason that it’s the de facto rifle chamber for the 69-80 grain bullets favored by AR-15 match shooters.
It’s also a great option for shooters who just want to maximize their rifle’s versatility in general– a .223 Wylde chamber will reliably shoot any .223 or 5.56 ammo you feed it, from the cheapest factory loads to the heaviest match-grade ammo. There’s something to be said for having a rifle that can go from hunting hogs in deep brush to punching paper at 500 yards without breaking a sweat.
At the end of the day, .223 Wylde makes a very compelling case for being the ideal chamber design for the AR-15 platform. By simply combining the dimensions of the 5.56 NATO and .223 Remington chambers to maximize the benefits of both, .223 Wylde offers a chamber that can feed and effectively stabilize a wider variety of ammunition, avoid any pressure-related issues, and maintain both the accuracy of the .223 cartridge and the muzzle velocity of the 5.56. Whether you’re investing in a rifle for hunting, self defense, or competition use, there are only upsides to choosing a .223 Wylde chamber for your AR.