What should be the headspace on a 460 XVR?

What should be the headspace on a 460 XVR?

It should be the same as the .45 Colt and .454 Casull casehead that it is based on. 0.005" to 0.006" maximum between casehead and recoil shield.

I've taken measurements on my XVR.
With cylinder pushed to the muzzell.....B/C gap=0.006"
Headspace=0.014"
With the cylinder pushed to recoil shield...B/C gap=0.012"

so, I have 0.006" worth of endshake and 0.008" to 0.014" headspace depending how you look at it.

Is it time to send the gun back to S&W to be tightened up? Also with slow deliberate trigger pulls in single action, I get some trigger creep on most every shot. That is actually very bothersome not knowning when the connon will go off. My 4 other Smiths have nice, crisp, clean breaking trigger pulls.

I don't have an X frame to take measurements with, but your endshake, BC gap and headspace seem excessive to me. How many rounds have you fired through it? How is the barrel throat holding up? When the X magnums first came out, I remember S&W sending out service bulletins advising that the barrels be changed every 1500 rounds? I'd call S&W service, give them your numbers and ask what they recommend.

Only 250 rounds perhaps with half being being full pressure rounds. I have a little flame cutting on the top strap and just a little erosion on the outside face of the barrel. It really just rounds off the forcing cone edge.

I just got off the phone with S&W. They are going to send me a shipping lable to send the gun back for repairs.