Steel is best used at high velocities, but I had killed several birds quite dead with the older steel loads at about 1250 fps. One was in the old 2 3/4 inch mag. High velocity is also better with lead loads as I ahve used a very effective 16 bore load on pheasants using 1 ounce of lead 7's at about 1400 fps. Seems be more effective than a 1 oz 20 bore laod. But with BP velocities are down with ITX, Bismuth or Nice Shot also. Ranges need to be shorter and pattern development needs to be more critical. Steel will work but ranges should be at about 30 yards, which is decoying duck range and so forth. Both geese and ducks have been brought in with BP steel loads. You might find that steel is more effective than you think. A 1 1/8 oz steel load will be more effective than the old soft shot duck and pheasant lead loads at 1 1/4 oz. BP shotguns should be used with slightly heavier pellets to make up for velocity loss. #3 lead shot was very popular in BP days which is very close to #1 steel. You do not hardly see any of it today but it was supposed to be death on mallards.
DP