*twodogs*

My experience:
Blind calling with a grunt usually produces younger deer (spikes & fork horns) and it works best as other said, right at sunrise / sunset.

Grunting at a buck during the rut will usually turn him unless he is locked with a hot doe. I've had better luck using a snort wheeze, especially if the buck is with a doe during the peak of the rut but that buck will usually not wander far from the hot doe.

I have had very little luck blind calling 140+ class deer, my thought is they don't get to be that age without limiting the number of chances they take.