The Real Reason for Pressure Issues

Over the years I've heard many, and often times, erroneous claims about 5.56 military ammunition being too high pressured to be fired in a rifle chambered for .223 Remington, or at the very least, misinformed as to the real problem. And while there can be minor differences in the amount of powder being loaded, the two cartridges are identical on the outside.

The real problem is not the cartridges but the chambers of the two barrels.

Chambering a cartridge loaded to 5.56 specifications in the .223 Remington chamber will force the bullet back into the cartridge case resulting in dangerously high pressures.

This is due to a shorter throat,

The Effect on Accuracy

The irony is that the longer throat design that allowed the ammunition loaded to 5.56 specifications to perform safely, also led to a decrease in accuracy.

The longer throat design used in the 5.56 chambering is of European influence, and I suspect that Eugene Stoner, the father of the AR-15, and all of the engineers involved in the evolution of the .223 that began in the 1950s never foresaw that a longer throat design would lead to lesser accuracy when fired from 5.56 chambered rifles, than the round is capable of.


Don't Throw Your 5.56 Aside, But...

While our company no longer offers 5.56 NATO barrels except on special order, I'm not saying that the accuracy is so bad that you should get rid of your 5.56... I was able to qualify Expert in Army Basic, and I'm by no means the best shooter out there.

What I am saying is that if you're buying a New rifle, or buying a New upper assembly, you should buy from a company that uses .223 Wylde barrels.

The .223 Wylde Solution

I'm not completely sure when the .223 Wylde chamber design first became available but I learned about it midway through 2012. Bill Wylde of Greenup, IL came up with the solution to better accuracy that bears his name.

I've heard and seen questions asked about the .223 Wylde "caliber"... It is not a caliber it is a chamber specification that improves on the throat area dimensions.

The changes that Mr. Wylde implemented have led to a huge improvement in accuracy as well as eliminating the need to worry about shooting 5.56 out of a rifle chambered in .223. Just make sure it is not chambered .223 Remington.

I've spoken to many everyday shooters who've purchased .223 Wylde, barrels, upper assemblies and complete AR-15s that rave about achieving sub 1in grouping with their everyday firearms.

By moving to .223 Wylde you are in effect moving to "National Match" configuration.


I didn't write this article to be a technical bulletin, but for those of you interested in learning more, there are several great Wiki references about Eugene Stoner, the evolution of the .223 Remington cartridge, and the .223 Wylde.

For anyone who has ever had someone try to convince them that the .223 and the 5.56 cartridges are different sizes... you'll especially enjoy the .223 Wylde Wiki.


Wednesday, July 12, 2017 by Madison James      Updated: Sunday, December 16, 2018