The metal in a good condition vintage LC Smith will probably handle modern loads. Shooting them particularly in a light 16 G is another matter. So few factory 16 G loads out there choices are limited most are loaded like light 12s and intended to cycle autos. RSTs are intended for SxS guns and work well, others kick too hard and generally have shot loads heavier than needed for Clays or upland birds.

I shoot Herters 1 oz 16 g shells in a pump the reload the hullls 3/4 or 7/8 oz depending on the gun. Lighter older Parker Hammer 16 stick with the 3/4. Newer Parker Trojan 3/4 for close range clays with some 7/8s in the pouch for longer shots.

Much easier on my shoulder and old wood. I am pretty sure a steady high volume diet of factory 16 g shells would cause stock problems in My Hammer Gun Your Smith likely the same

Others may see it different.

Boats