I was hoping that another member may have some insight into this rear sight blade arrangement on my Pedersoli 1861 Springfield rifled musket. The 300 yard leaf is a no-brainer but the slot on the 500 yard leaf is an enigma. Notice it also has a hole which I assume is a calibrated sight/range hole for sighting. Pedersoli has not answered any of my three emails asking for clarification on this rear sight. None of their literature or web images show this particular sight leaf arrangement with a slot on the 500 yard leaf. Have any of you seen this before and used it?
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