Depends on the quality of the gun (wood, engraving, etc.); it has to be pretty nice or the cost of sleeving wouldn't be worth it. I have a sleeved Coggie sideplated boxlock that was one of a bespoke pair made in 1906; it's a very nice looking, nice handling gun, and the only effect sleeving had on it was to drop the market value down to where I could afford it.

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