What a fantastic starter gun for a young lad! An H&H! I hope he brings down a double gaggle of pigeons with his new gun. He won't care one bit about the weight or what it was in it's former life. He'll just be one thrilled boy!
I would imagine that the reason this was done is that the barrels were either shot out or rusted out, so really they were just making the best of a bad situation. Economics were obviously a consideration or they would have re-barreled the rifle.
Regulating rifled barrel liners would be a very difficult proposition. I have relined a bored out rook rifle to a .22 hornet but that's simple compared to a double rifle.
