Blake drill and the Enos drill are great transition drills for this. I have learned as most seasoned shooters have that smooth is fast. If you are forcing it, it likely doesn't get a good result. What you do has to be repeatable. Dry fire is great practice. You can put up post it notes or playing cards for targets at varying distances. Just like the draw, you train yourself to bring the sights to your eyes. Memphis said it perfectly. Slow it down for your brain, and remember that smooth really is fast.