Do you love high-volume target shooting with both .223 and 5.56, notwithstanding the (relatively) minor differences between the two cartridges?
Then you need to make at least one build with a .223 Wylde upper. Here’s why, down to the details.
First Off, What Is a 223 Wylde Upper?
First, we need to clear something up that seems to have spawned some questions out there. Unlike .223 Remington and 5.56x45mm NATO, .223 Wylde is not a cartridge.
It is a chamber. Specifically, it is a hybrid chamber that can accept both .223 Rem and 5.56 NATO.
Now, why would you want this when you may have heard that these two cartridges were effectively the same?
Well, because they are not the same. Even though the dimensions of the two cartridges are (basically) identical, chamber pressures are not.
The .223 Remington can produce chamber pressures of 55,000 PSI - not so for the 5.56 NATO, which can produce slightly higher pressures at 58,000 PSI.
The word here, slightly, should not be underestimated in accordance with its conventional connotations. In this application, though the pressure differentials might be considered slight in an absolute sense of the word, in practice, they can be disastrous.
Firing an 5.56 NATO cartridge in a .223 chamber is not going to go over well and can even result in catastrophic failure of the action, barrel or both, which can have fatal consequences for the shooter and bystanders.
With that said, it is generally accepted as safe to fire a .223 in a 5.56 chamber - but never the other way around.
This can result in a fairly sticky situation if you ever have both .223 and 5.56 cartridges around at the range as, without looking at the headstamp, you won’t be able to tell them apart.
This is why a 223 Wylde upper is a great thing - it eliminates guesswork. The advantages go beyond this, though.
Why Would You Want to Build with a 223 Wylde Upper?
If you already have an AR chambered in 5.56 or .223, why would you want to shell out the dough for an additional build for a rifle with a hybrid 223 Wylde upper?
Well, for one, it’s safer. As stated, there’s no risk of firing either of these cartridges through the rifle. It will happily feed, fire, and eject both of these cartridges with no problem. There’s no risk of accidentally chambering the “wrong” one, so you can have a bucket of .223 and 5.56 next to you and have at it.
But safety is only one consideration, however important it is. Consider also availability.
For those of you that practice high-volume competition, let’s say you have a preferred .223 rifle. That rifle cannot safely chamber and fire 5.56.
If you didn’t notice, the price of ammo has skyrocketed while availability has generally tapered off. In some instances, certain oddball cartridges are not only cost-prohibitive to purchase but generally impossible to find.
Not the case with .223 and 5.56, but prices are still elevated and if you can’t get your preferred .223 round, you’re out of luck.
Unless you have a hybrid chambering, as is the illustrated case here. The thing about 5.56 is, as a military caliber, even if prices are high, you’re never going to be far from some (or a lot). This is one of those calibers that most gun shops never run out of.
If you build a rifle with a 223 Wylde upper, it also means that you can substitute 5.56 for your .223 and be on your merry way.
This also brings up the benefit of convenience. You won’t need to be guarded at the range to make sure you’re not chambering one or the other - both will work just fine in your rifle if you go with this hybrid chambering.
It could also potentially save you money as you can curate what cartridge you fire based on intended complication - save the pricier ammo that offers better performance for competition, long-range shooting and hunting and use the cheaper 5.56 for plinking, training, and high-volume target shooting.
Is There a Downside to .223 Wylde Upper?
There really is no downside to building a rifle with a 223 Wylde upper especially if this is your caliber of choice, since it can shoot both .223 and 5.56.
Some argue that .223 Remington is inherently more accurate than 5.56, and even if so, most rifles chambered in 223 Wylde will give you similar performance. Perhaps you will notice minor differences between the two cartridges, but at the very least you will still be able to plink affordably with 5.56 if you ever have a hard time finding .223 Remington.
What Size .223 Wylde Upper Should You Choose?
That depends almost entirely on the intended application of the rifle. If you intend to build a rifle for defensive applications, then you should choose one with a shorter barrel. The shorter barrel will make a much lighter overall platform and will handle better, especially in close quarters.
As for sporting applications, specifically hunting and long-range shooting, it’s probably a much better idea to go with a .223 Wylde upper with a longer barrel, like a 20-inch AR upper (that link is for 5.56 only, though).
The longer rifle will be heavier, making it harder to carry and handle, but it will also be much more stable. Most shooters also find that a longer barrel helps with accuracy at extended ranges, and as for hunters, the longer barrel will produce a substantially higher muzzle energy, which will produce better stopping power.
Start Your Project Here
Getting ready to create your ideal modern sporting rifle with a .223 Wylde chambering? Get your parts and kits here at MCS Gearup. We carry a wide range of assembled uppers, lower parts kits, and nearly complete build kits along with all of the parts you would need to complete the build piecemeal anyway. Take a look through our catalog and get in touch with us at Sales@MCSGearup.com if you have any questions.