Double vision

[SBL]

Cleaning the gun this morning after having a bit of a torrid time in the dark and rain last night.
Mounted the gun a couple of times afterwards and noted that I’m seeing the end sight in double in my peripheral vision. If I look at the sight directly it remains as single. I’ve never really noticed this happening before. So I start pointing my finger to check dominance and find that if I look at my finger then I’m right dominant. If I look at the target with my finger in peripheral vision I have the 2 fingers. If I look at the left finger of the 2 my right eye is dominant and remains so. If I look at my right finger of the 2 then my left eye is dominant and then remains so.
I’m now completely puzzled, help!

 

[eightlittlebits]

Entirely normal, called physiological diplopia, also known as "normal double vision".

If you're right eye dominant you use the left image.

 

[Westward]

As above. This is one of those things where the K.I.S.S principle applies.