I recently picked up an old Leupold 16X AO Target Scope w/ Fine Crosshair and need a little help with it. How do you adjust the turret to zero after zeroing the scope? Not sure if middle piece is a cap with a screw under it or if there is a pull up type reset or set screw someplace. There is a line etched on the scope housing where marks on the turret line up but I'm struggling to get the 0 on the turret lined up with the index mark on the housing. Thanks.
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