Canuck not sure if you are directing that to me????? But if you are, when you get into the sport of SR Bench Rest and I mean at the competition level and shooting custom actions a person who knows his way around a lathe and measuring devices,does not need your action to headspace each barrel every time.
BR shooters who use gunsmiths around the country do not send there entire rifle every time they need barrels chambered. They take measurements, keep a file on that particular serial numbered action. When they need barrels chambered up the customer orders the blanks, and have them shipped to the gunsmith they use. The fellow I use, has my reamer and cuts ONLY MY chambers with it. The first barrels he did after the initial build he verified with the go gauge. It was bang on. This was just chambering to the measurements he took off of the first barrel. Like I said after that there has never been a chamber shorter. If anything they have been slightly longer and the most was ever 2 thou.
That is all I can tell you. I am not the machinist/gunsmith. This man knows his way around a lathe. I have seen some work he has done and he leaves NO stone unturned. He shoots BR as well.
Fortunate for me and unfortunate for others that he keeps his client base small.
I get 2 barrels, cut to length, chambered, threaded, crowned and outside finished for $1+1+1,3+2, 0............................. ;-)
Honestly, I read all to often that BR shooters are arrogant. Well I would tend to agree in one regard. When we need something in regards to bullets, barrels, powder, etc........... or where to find things, or who we may use for our work we are real careful with that info.
Bottom line, guys need to work together.