Even though Tiger Woods didn't win the U.S. Open this past weekend there was some great footage on the broadcast of his "stinger" shot. They were showing the club face coming into contact with the ball via a camera that was shooting some crazy number of frames per second like 60,000. It was very interesting to see the position of the club face at impact and see what the club head was doing through the hitting zone. It was also interesting to note how "quiet" (as in not moving) Tiger's feet were. Let's talk about how to hit a long iron stinger shot.
When I'm hitting this shot the first thing I do is move my ball position farther back in the stance. Where a long iron might be inside the front (left ankle for right handed players) ankle, I might put the ball more toward the ankle of the back foot (right foot for right handed players). This changes the angle of the club face to a less lofted position at impact and makes the ball launch lower.
My feet in this stance tend to be setup in a slightly open position, with the front toe pointing toward the target.
The shaft of the club will be "de-lofted" at address naturally because the ball is back in the stance and the hands come down to the middle of the body to grip the club.
I bring back the club just like normal, but I stop before parallel or a full swing. Some methods suggest this technique and others say to go ahead and take a full back swing. The length of the back swing isn't as important as what happens at impact.
Delay releasing or turning over the hands until impact and focus on keeping the club de-lofted through the bottom of the swing. It helps to finish low, which makes keeping the club de-lofted easier. Finishing low also helps promote a lower launch angle.
Though finishing low, it is still important to accelerate through impact.
The result should be a ball which launches with high velocity and low trajectory. I find the shot not terribly hard to hit when you get the hang of it. The stinger can be a great "go to" shot when you absolutely must hit the fairway or in windy conditions when you need to keep the ball low.