I measured myself, and I'm 8.75" from tip of thumb to tip of pinky.
But why is that relevant? We're mostly concerned with trigger pull, right?
Therefore, what we're really concerned about is distances from the base of the thumb at the web of the hand to the first knuckle of the index finger.
I have odd fingers, for instance; my pinky and index finger are pretty short, and the middle and ring finger are pretty long. So gripping the gun is comfortable, but the DA trigger pull is just on the long end of "doable."
I'm about 4-3/8" from the base of my thumb to the first knuckle. I would say that a measurement of less than 4-1/4" is going to mean trouble getting a good DA trigger pull.
