There was an article in the Oct issue of the Pennsylvania Game News about sighting in a scope on a crossbow. I imagine there are several ways to do this but here is my take based on the article.
Put the xbow on a solid rest and use the crosshairs to sight it in at 20 yds. Adjust the windage and elevation knobs to zero it in. Go to the next lower crosshair and shoot from 30 yds. If the arrow hits high, move back. If the arrow hits low, move up. Do not change the scope settings. Once you are hitting the bullseye, measure the distance, then go to the next crosshair and shoot from 40 yds. Again adjust your distance to hit bullseye. Keep doing this up to your longest range crosshair. When you are done, write the distance for each crosshair on tape and put it on the bow. The distances for the crosshairs may vary, i.e. 20, 32, 44, and 56 yds.
Some scopes have a speed dial. For them, you sight in at 20 yds then shoot at 50 yds using the appropriate crosshair. If the arrow is high, you turn up speed dial. If arrow is low, you turn speed dial down. Once you are set for 20 and 50 yds, it should be good for all ranges in between.
Hope this helps. Good luck.
Last edited by another_pilgrim; 01-19-2019 at 01:30 PM.