Randy,
With modern plastic shot cups and steel shot less likey to rust into a single slug a barrel bulge is unlikely. That stated, any gun not made for steel shot could suffer a loose rib even if the chokes are opened to IC or Skeet. Will it happen if one shoots a box or two a year of #2 or smaller shot? Probably not, but it could. We would use a gun such as a Bernardelli or even a Model 21 with steel shot at our own risk.
Now, I recently saw a LC Smith Field Grade with cut barrels (little or no remaining chokes) for sale. I thought about buying it to see how long the ribs would hold with steel shot. I opted not to waste the $600 asking price (a bit high) on an experiment.
Mark
