None of those .224" offerings you mentioned turn my crank so I'm forced to opine about 6mm's...

I would do a vanilla .243 and run 55's very fast or 75 really fast.

Or if you want to do something out of the ordinary (I'm assuming this is the case with your 6mm chambering mentions above) I'd Ackely it...grin...

A .204" fast twisted shooting 55's could do it for me too -


- Greg

Success is found at the intersection of planning, hard work, and stubbornness.