When I was starting out in handgun shooting I had a Highway Patrol officer friend who accompanied me to the range. He saw my shooting and noted I had ”decent” groups, but they were trending low of the bullseye. He asked if he could have me shoot his revolver and let him watch. He put 4 live rounds in the cylinder and two empty cases in there at random. When I hit the empty shells you could see the muzzle dip.
He told me I needed to concentrate on trying to keep the front sight in the middle of the target through the whole shot, and follow through after recoil.
We repeated the exercise several times until I stopped nose diving the muzzle on the empty rounds. I then shot my pistol and was shredding the center of the target.
Using fired shells in revolvers or slipping snap caps into the mag of an autoloader Can be a useful exercise.