I started off as a trained watchmaker.
I sort of fell into gunsmithing in a jewelery store that sort of fell into doing gunsmithing.
We wound up as both a jewelery store and a trade shop for gun shops.
My specialty was restoring Colt double action revolvers to factory condition but I did most anything that came in.
The owner did shotgun work since he loved fine shotguns, and the jeweler did rifles and black powder.
I sort of took care of the "black" guns and pistols also.