Both of my xbows are deadly accurate to well over 50yds but that doesn't help much when deer are likely to duck the bolt much over 30-35yds because of the noise! (If it's thick then obviously distances are much less than even that)
If I were in a situation where I wanted to shoot deer 35-50yds with archery equip then I'd use my Mathews Switchback XT instead of my xbows. That thing is silent and deadly accurate as well but I just refuse to shoot at deer that far away, just to much can happen with arrows/bolts at such distances. Punching paper vs hide at 50yds is two entirely different situations!