That isn't really an old gun (gun wise). It'll be fine. I never shot a gun newer than that at turkeys for years (5 different ones). They will handle mag loads no problem. I used steel shot through my full choked 1918 nickel steel model 12 as a teen and that was a bad idea.

I have my granddads model 12, it too is a 1918 model. I've been toting it some. I've patterned 2 3/4 TSS 9s through it.

Mine was also my grandfather's. it has shot a ton of game from waterfowl to deer. I have a picture of him with a nice buck and that gun in Missouri's first deer season. It later was my grandmother's and she shot her deer and turkey with it for ??? 50 years. I shot a couple deer with it and some turkey too, but screwed the barrel up in the early nineties shooting geese and ducks with steel ...kind of took the full out of full choke.

Stories of it backing off thieves and possibly shooting a man protecting the trains during WWII make it a special gun to me. One time a man killed a HP officer and stole the patrol car. Sheriff called my grandmother and said he is coming your way so get ready. She took the screen out and waited. guy pulled down her drive but lucky for him he decided not to steal one of her cars. He did open the door but never got out. She told me the safety had been clicked off but she was real happy he drove off.

The story is that it was purchased through Montgomery ward for $1 a month for 12 or 16 months.