I bought a shotgun made in 1909 just over 4 years ago. I should never really have bought it as it was such a poor fit for me, I just couldn't get on with it. I had put about 30 cartridges through it in 3 walked-up outings then decided to sell it. Imagine my surprise when I was told by a gunsmith who was assessing it for a potential buyer that, and I quote 'whoever refurbished the barrels has done a mind numbingly and unbelievably bad job' and 'it's a beautiful gun but the barrels are scrap'. Gunsmiths had also stated that it was 'unsafe to shoot' due to the minimum barrel thickness despite having passed proof after its refurbishment.
After a long drawn out process which has seen the gun and barrels travel up and down the country to various gunsmiths to argue over the barrel thickness, the dealer I bought it from finally agreed to take it back with a refund. It was ticketed as 'mint' when I bought it.
So a word of warning to anyone who is tempted to buy an old gun, irrespective of whether it has passed proof, have the barrel thickness measured and check the gun out thoroughly. Particularly if the gun has been refurbished.
I've been lucky that it did not split the barrels when using it and received a refund.