.223 Wylde (Chamber)

The .223 Wylde chamber was designed by Bill Wylde (a gunsmith from Greenup, Illinois), in order to keep the accuracy benefits of a .223 chamber, while safely avoiding excessive pressure buildup when firing higher-pressure 5.56mm NATO ammunition. As a result, guns with a .223 Wylde chamber are typically safe for either .223 or 5.56 ammunition, and in theory, should produce better accuracy across the board.

What is .223 Wylde?

To understand the rationale behind the .223 Wylde chamber, one must first understand the differences between the .223 Remington and 5.56x45mm NATO. Despite some common misconceptions, these two cartridges are actually identical in dimensions. The difference, is that the 5.56 NATO is loaded to higher pressures. To alleviate the extra pressure, a 5.56 chamber has a longer (and very slightly wider) throat. And so of course as a result, firing the already lower pressure .223 in a 5.56 chamber is completely safe. However, the opposite is not true. Because a .223 chamber is not designed to handle the added pressure of 5.56, this can lead to excess pressures, potentially resulting in catastrophic failure of the firearm and injury to the user.

The problem is that although a chamber rated for 5.56x45mm NATO will properly shoot both types of loadings, it has one issue, especially when talking about precision accuracy. Because of the longer throat, there is a greater distance that the bullet needs to "jump" between its starting position inside the casing, to the beginning of the barrel's rifling. This theoretically decreases accuracy. Bill Wylde's ".223 Wylde" chamber, tries to bridge the gap and obtain the best of both world. The higher theoretical accuracy of the shorter-throated .223 Remington chamber, and the larger ammunition selection that comes with 5.56 loadings, leading to an all-around more accurate chamber that is still rated to safely fire both types of ammunition.