This is probably a novice question, but here it is. I am waiting for the last component (the barrel) to arrive to complete a 6.5 CM build from a mod. 10 .243. Let's say, for whatever reason, I decide to screw the old .243 barrel back on the action. Will I have to start load development all over again for the .243? In other words, I suppose the head space would probably change just enough for original loads not to be all that accurate anymore.
Thanks in advance.