I've noticed a very bad habit in myself that I can't seem to break, and it leads me to losing a ton of gunfights. I tend to start shooting just a FRACTION of a second before my movement penalty is up, and this often leads to my first bullet going stray, and my accuracy for the rest of the gunfight to be less than ideal, even if my crosshair placement is good.

How can I practice getting the timing right for highest first shot accuracy? I feel this wrong timing has been ingrained into my muscle memory and I need a way to "reset". Any advice?