With my bow never. With my rifle I have never had to shoot one in the head but have taken a couple of neck shots when circumstances called for it and they proved to be extremely lethal.

As far as head shots, where I hunt a lot of counties are buckshot only,if you give me my 3 1/2" 00, inside 35-40 yards you can cancel Christmas for any deer on the receiving end of that load. I have killed numerous deer with that combo and it is devastating. I don't necessarily aim for the head (more like the base of the skull where it meats the neck) but I'm sure it fits the head shot category.

Often times deer can carry buckshot a long way leaving a less than ideal blood trail (even when hit well) combine that with other circumstances like deer being pushed/run(adrenalin), impenetrable thickets/swamp, uncooperative neighboring landowners(no deer retrieval) and I will take a head shot (as described above) and be less likely to lose a deer to the above circumstance(which are fairly common in VA).