I know the pro's and con's have been covered extensively several times over. My question isn't whether to do it or not but rather when? Should it be done after barrelling in the event any possible removal of material trueing up the lugs could affect the procedure if done after? Thanks.

If you are going to do it, it should be done after some of the machine work is done to the action itself. So, yes, after the lugs are cleaned up, welding is done, or any other work that affects the original heat treat or destroys the case in a safety critical area (Lugs in particular).

I would not fit the barrel or square up the action until after the action came back, see below.

Re-heat treating will change the receiver dimensions a slight amount to a great amount. So, you will have to do a bit of lapping of lugs, etc. or even more after the receiver comes back. You can leave a small amount of extra metal in some area to accommodate this, or just hand fit afterwards.

Things like truing the C ring, front of the ring, or chasing threads should be done after it comes back, IMO. Even though it is more of a PITA to machine case hardened steel.

Jeremy

where do you plan to have it done?

I have them done at Blanchard; they process to RC38-40; not too hard.

the questions is, which "process" do they use?

Thanks farbedo, that makes perfect sense. dpcd, I'll keep Blanchards in mind. I see their name come up quite a bit on this topic.

Which process they use is the one that the customer specifies; also the hardness and case depth must be specified by the customer. That way, they are off the hook for them.
They heat the parts in a carbon rich oven (usually carbon monoxide), and quench, then heat again to draw back to the hardness you specify. The parts come back gray and rough; do not polish them before you send them as I did; total waste of time.
For example; if you want them annealed first, that is a separate operation and you will be charged for that. I just ask them what most people get done on Mauser receivers and they will tell you that. Then I say, "then do that to mine".

I had six done this summer; no warpage noted.