I am no expert, but this is what the experts say.
Flinching and blinking are habits developed from reacting to the blast and recoil of the shot. The way to replace bad habits with good ones is to establish proper shooting techniques (hold, indexing, trigger release, follow through) while eliminating the negative effects of blast and recoil. And the best way to do this is by dry-firing.
Many believe that the only reason for dry-fire practice is to save money on ammunition, or save the inconvenience of driving to a range. Certainly these are worthwhile benefits. But even if you live next door to a range and have unlimited access to free ammunition, dry-firing should be a regular part of your practice. Military shooting teams, which have those resources available, still spend considerable time dry-firing. The reason: Dry-fire builds positive habits. This has been well-documented by the best shooting coaches.
Bill Pullum (Lt. Col., Ret., U.S. Army), who coached Olympic and International U.S. shooters to unparalleled success, wrote: "Shoulder jerks, eye blinks, flinches of all types, delayed reactions and false starts can all appear in the trigger-pull sequence... when they do, trigger-pull techniques usually must be relearned from the beginning. This conditioning practice is best accomplished by dry-firing, which is probably fifty to a hundred times faster than any other method" (Position Rifle Shooting, Bill Pullum/Frank Hanenkrat, Stoeger Publishing Co. 1973).
I dry fire all the time, It’s a good way to practice off hand shots (especially with my wheel gun), concentrate on making sure the cross hairs are on the same spot before, during and after the squeeeeeze. Try different breathing techniques.
Just my .33 cents worth.