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I wouldn't recommend shooting steel shot out of that older gun, especially if it has a tight choke. Better non-toxic alternatives that are easier on your gun's barrel than steel are bismuth, Tungsten Matrix, Tungsten Iron, and Hevi-Shot (a combination of the other types), with bismuth and Tungsten Matrix being the closest in weight to lead. All are available in shotshells from various manufacturers. Cabela's, for example, carries the various types of non-toxic shells.
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