Once I have both bolts (6.8 and .223) I will check for head space variance.
Just like AR bolts, measuring lug and face. I have been lucky there as I have no more than 0.001" difference (lug and face) over several bolts for the 22 Nosgar (6.8/224V) and my 22 Nosler (.223 bolt).
Will start with the .243 barrel with the .308 bolthead for a month or two and change out when the Shilen 22N barrel gets here.
I don't expect to be changing daily :)

Just received my new AR barrel from X-Caliber.
Won't have time to assemble and get to the range before the next match so it's the old barrel for now.
Will borescope, pin, measure extension and mount in a BCA side charge upper.
Already looks like I will have to do my normal spray on shim thermal fit with the BCA upper (slips most of the way in).