Re: shepard scopes
A range card/sketch is a great way to have fast reference points. I make one for LR hides. Make it for points of interest, like where trails come into fields, certain trees or rocks your quarry may pass, etc. It doesn't have to be elaborate. I mark a spot, range it and figure in cosine, sketch it, and add on the adjustments for range/windage under it. Then you also have it for future reference. It doesn't take the place of a range finder, just faster for key spots.