.223 Wylde is a hybrid .223/5.56 chamber designed by Bill Wylde to yield the
accuracy advantages of the match .223 Remington commercial chambering but
without pressure or reliability failures when using high velocity 5.56 NATO spec
ammunition. The .223 Wylde achieves better accuracy by having a chamber throat
that is tighter than 5.56 but will still function reliably with military 5.56
ammunition as the case dimensions are the same.