I just picked up one of the Redfield revenge 2-7 crossbow scopes, used. If anyone has a manual or a source for one, it’d be appreciated. I don’t foresee using it for the ranging function much…but when I search on it, folks talk about a ‘speed ring’ and zeroing for various crossbow velocities, without any specifics. I’m ‘guessing’ that you just zero at 20, and figure out at what specific magnifications your drop hashes correspond you your crossbow drops? ….basically manual rope for the hashes. Anyway, any help appreciated. I’m pretty sure the range reticle line is similar, in that you have to do some calibration at a known range with a known animal vs the reticle opening?