The new Fabbri guns are supposed to be built to withstand firing a 12 bore gun with a 20 bore shell in the barrel without sustaining damage. It’s claimed that zero change to the barrels occurs. I don’t know. I have never tried it. Don’t plan on it.

Nor do I plan on playing Damascus roulette. Cannot see myself doing surgery without the use of my hands. I’ll just buy guns with modern steels built after WW1. Guns that remain in proof and excellent repair.