I believe that the conventional wisdom, proven to me by my own experience, is that your fixed sight SW will shoot to point of aim at 25 yards with a 158 grain lead bullet. A lighter bullet will shoot low. That said, the accuracy with a 148 grain full wadcutter is unparalleled. Your mileage may vary, but not by much. Unique and Bullseye can't be beat, but may be matched by HP-38/Win 231.

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Some collect art; I shoot it!