I used to struggle with the same distances. I would have much rather been 125 yards out than 75. I would either decelerate a 3/4 backswing or try to muscle through a swing guessing at where I needed to take the backswing. This caused much inconsistency with my shots.
The breakthrough for me came when I changed my thinking from "how hard do I need to hit this" or "how much do I need to take off the shot" to simply "how much of a backswing do I need". I practiced taking backswings where my left arm was parallel to the ground then tried a swing at roughly 6 inches below that. The key for me was swinging normally (accelerating at the speed of a normal shot), not decelerating or trying to muscle through the shot. By taking a normal shot (left arm parallel to ground) I was able to get the feel of the acceleration I wanted for the shot with the backswing 6 inches below that. Alternating back and forth until I felt comfortable.
Once you get the first In between shot down it's easier to then decrease the backswing yet another 6 inches or so. Find the spots in your backswing that you feel are 1/4 swing, 1/2 swing and 3/4 swing. Once you know how far those go you can fine tune even more by going slightly over or under a 1/4, 1/2 or 3/4 swing.