I have had quite a few guns CCH over the years. Most of them had no warpage or a very slight amount, knowing how to hard fit parts comes in very useful.
I recently had a breech block done. It had a striker disc in it which had very fine threads. It did not move much but the disc did not want to go back in. Lots of patience, a diamond file here and there and some lapping compound did the job. The lower legs on the block spread just enough to not go back in the action as well. Some very gentle work in my machinist vise fixed the issue.
For me a very important component of the process is ending up with a hard skin. If you quench at so low of a temp. to completely avoid warpage this hard skin is not present.
Always do wood work first, metal finish last. Any other way is a headache.
