I have a set of 16 gauge barrels which are dimensionally (outside dimensions) the same as the barrels on my old hammer Manton (of Calcutta) 20 gauge side by side. My gunsmith says he could easily fit the barrels to the action. He has fitted many 12 gauge barrels to 12 gauge actions of differing makes and they are very much in use today. My question is would I be endangering my gun in any way by doing this?

Thanks for your help.

Skeeterbd