Setting pins and grouting the machine to them is basicaly locking the machine to the floor , uless you want to drill threaded anchors and screw the machne down to them that sounds like a very solid mount. If he is willing to do it for free and he knows what hesdoing then I'd let him (just remember , nothing is ever free) If he does this kind of work at a CO2 station then he has probably mounted alot of compressors which generate ALOT more viberation than a lathe will.
A for indicating off the firing pin hole I'm not sure how hes doing that , a live center in the pin hole?
in order to true the action back to blueprint you need to find a common medium for the bolt and the reciever ,in this case the bolt body and bolt race way , you setup your mandrels in the action and dial the action in to zero on the indication rod , both at the action face and at the far end of the rod , this insures that your action is running true on the bolt race way , you true the internal lugs , chase the threads out .010" and true the reciever face now the reciever is square to the bolt race way , the bolt itself needs to be indicated off of the bolt body , their is a couple ways to do that , either with a jig that holds the bolt back close to the handel and exposses a bit more than half the bolt body so useing a spud that screws into the rear of the bolt so that you have somthing to clamp the chuck onto then using a collar over the bolt head set it up in the steady rest ,use a dial at the rear of the bolt by the handle and one up behind the head dial it in to zero then cut your rear locking lugs , the bolt face , nose , and front of the lugs so its just leaning up the surface now the bolt head is square to the bolt body and everything is back to "blueprint" ,but like I say theirs a bunch of differant way it can be done.
Some people don't do antyhing to the action except true the face up a little and hand lap the lugs , they claim that its a waist of time and as long as the chamber is cut properly and the barrel is good you can set the round off with a hammer and it'll shoot , again how do you argue with a track record like he has?
I've got all your stuff in my garage and can load and unlad it with a little chain fall I have in their ,no worries on that. , Anybody up that way looking for a good 12ga , perfect for running dogs , turkeys of 2 legged varmints.
I'll give you a call Monday if your planning to go see the old man I'll treat to lunch
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