Pilgrim:

No, it has nothing whatsoever to do with age.

On a trip to England back in '92, I unexpectedly had a few days to kill in London, so I spent the time making the rounds of the London gunmakers. David Winks (formerly Holland & Holland shop foreman) told me the story of a new Royal .465 they had recently built for a customer that was to be used primarily for elephant hunting. The client insisted that the rifle be regulated with monolithic solids. Such bullets were still relatively new then, but enough DRs had come through the shop with overstressed rifling for them to figure out what was causing it, and Holland begged off responsibility if a problem arose. By the time the regulator had finished his work, visible, severe overstressed rifling was present and the barrels were scrap. The client was out the cost of new barrels. This was a brand new rifle, unfinished and still in the white. Not long after, Ross Seyfried included the story of this gun in a DGJ article. A couple of years ago, a good friend had the occasion to check into the cost of re-barreling a Holland .465. It was close to $30,000 then. Do you really think Holland uses anything but the best chopper lump blanks?

I heard from a fellow some years ago that was shooting Barnes X in a new Chapuis 9.3. The ribs came loose. Chapuis fixed it, and he went back to shooting the X. It happened again, and Chapuis balked at fixing it the second time. When he told them what he was shooting in it, they said "Oh. Don't do that any more." The perceived benefit (entirely mental) isn't worth it.

You might want to consult the folks at Champlin. They sell Chapuis, and J. J. Perodeau has his shop there. J. J. is a Liege trained gunmaker who works on double rifles every day, and has seen just about every kind of DR barrel malady there is. He re-barrels DRs. Pretty sure he is one of Chapuis' warranty guys in the US, at least I know that he has done warranty work for them. I can tell you just about word for word what he will say.
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