On a single barrel gun, you can ring the barrel at the choke, and not much will happen. On a SXS, if you ring the barrel it will separate from the rib and the repair will be worth more than the gun. These barrels were never designed for steel shot. Opening up the chokes is a reasonable way to proceed if you want to shoot steel, but how much? There is precious little data available on how much to bore out Spanish 10 gauge chokes in order to pattern steel shot. Take out too little and you could wreck the gun, take out too much and you have a nice short range 10 gauge. Until some hard data is collected, I will stick to the Bismuth hand loads, and hope to get my Tungsten Polymer loads some day. In my mind, it is not worth risking the gun for the sake of steel shot. I am interested in your results if you do open the chokes.
Sharptail