Re: bushing a firing pin hole in a bolt
It will help mask pressure signs such as primer cratering, but it is not strengthening anything. It just leaves less primer unsupported.
You are correct as to the procedure. It is a pain and I have no idea what anyone charges, but if it is under 150 it is a bargain as far as the smiths time IMO. I probably will not do anymore. I would rather opt for a PTG oversized bolt if I am rebarreling one.
I admit that I know just enough to be dangerous.....but dangerous at ever extending distances.