Great Blog by Oleg Volk on Eye Dominance
Aiming a pistol is easy even with a cross-dominant eye
Using the dominant eye with open sights
About 10% of all people are left-handed. About 30% of the population has a dominant left eye. In quite a few shooters, the left dominant hand is paired up with the right dominant eye, or the right hand and left eye. When shooting pistol, that mismatch is easily overcome by a slight shift of the head position. With rifles and shotguns, cross-eye dominance can be a problem. Closing the dominant eye to use rifle sights is uncomfortable and feels unnatural. Worse, a shotgunner pointing with both eyes open won’t get a good reference for the barrel position: instead of seeing the bead at the end of a rib, he might see the side of the barrel as the wrong eye asserts dominance.
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