@ 806guns,..
You can try it, on New Petersen cases AND,.. Use, the "Go" Gage to "double check" them, just in case, the Petersen cases, turn out to be,.. "Small". ( You want the Cases to Fit well but, RELY on, the Go gage ! )
I used, 2 New Norma cases that, I "felt" were, Dimensionally, "Correct" to make sure that, they Fit and, then, Bolt "almost" closes on, the Go Gage ( went down on it about 1/2 way, VERY, Tight on Go and Stopped ). Then I put, 2 thin, Layers of Electrical Tape ( About .006 - .008 Thick, combined ), on the Back of the "Go Gage" for use as, the NO Go ( My Bolt, wouldn't even, Start to close, on IT ). The Key is getting Bbl and Nut screwed down with Bolt closing "Tightly" on, the GO Gage to,.. barely close on it .
I used, Blue Lithium Grease on, the inside of, my Action ( on, the Threads ) and a couple of Drops of Blue Loctite on, the Nut's inside, threads. I De-greased everything, FIRST ( Lithium allows, the Barrel to come out, later, IF desired and Loctite on Nut threads, doesn't let it work "Loose" from, Recoil / Vibration.
Approx., 200 Hundred Rounds thru my Rifle and NO "Issues" with Headspace or, Case,.. STRETCHING.
There are a couple of, Vids on YouTube to, "double check" the Process ! I'd watch them, BEFORE attempting !
I wrote down Everything down that, I wanted to, DO,.. step by Step from, Notes taken, on Vids.
Once, the Case is IN your CLEAN Chamber, Torquing the Nut, becomes, a little "Tricky" to get the Proper, HS "Fit" so don't Crush, the Brass cases, as Torquing the Nut, will make "Things" even, tighter ( Check and Re-check THIS stage ).
Good Luck and Be,.. Safe !