Hi Gary, I have one reline under my belt, with two more waiting. If you have the right tooling it is a fairly simple process. I used my lathe, piloted drill bits (Pacific tool and Gauge ) and a TJ liner. My #4 Rolling block shoots pretty good. I had an extension rod welded to the drill bit to get through the barrel. glued the liner in with red Loctite( I can look up the # if you need it) Then re-chambered, cut the extractor with a file. I don't know the particulars of a low wall, but the barrel relining should be the same. A google search for gunsmiths to reline should give a few names, and there are a couple youtube videos on it. I preferred to stay away from the handheld drill method, but that's just me.
Are you wanting to change the caliber or just get rid of a rusty chamber? Also is it a 38-40Win (short cartridge) or 38-40 Remington (longer cartridge)?
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