The suggestion about glasses which will allow clear focus on the front sight is a good one. I had a set made for me by an optometrist. Plano lense for the left eye and a dioptered Rx lense for my shooting eye.
I was also able to find an inexpensive set of those drugstore reading glasses that do the same thing. Look at those first.
"Only hunting and mountain climbing are sports. The rest are just games." - R.Ruark
NRA Life Member