Mike has a round thats 6mm thats a bit more than the WOA too... I tend to call my 6woa a 243 short as its not as fast... but works fine to 200 yards.
I have a Dtech on the list, I've heard and read enough about them and my smith, WOP, suggests them for the wssm rounds and says Mike is a superb smith period...
Others here have Dtech uppers and will chime in.