If you use a head space guage the bolt should just touch the barrel, I bought a box (50) dummy cartridges from Brownell\'s and run them through to check. The problem is that you need to shorten the bullet if you leave the ejector plate in other wise the cartridge will hang up on extraction
Of alll the quirks of the build this was the one that drove me nuts trying to get right.
you end up getting a happy medium on the head space settings but they should not be off over a couple of thousands.
I ended up putting a 6-32 set screw in the main shaft adjusting nuts to keep them locked in place once I got the correct adjustment, be sure to put a piece of plastic or lead shot under the screw to protect the threads.