I had an optometrist that was a rimfire position shooter from way back. He still had his canvas shooting jacket, Win 52, and a case of 10x he bought for $95. WOW!
I was shooting NRA and IHMSA silhouette and I "specialized" in the standing positions. When I hit my later 40's my vision went from 20/10 to 20/40 in a year. Then 20/60 the following year with an astigmatism thrown in the mix. As my sight changed my doc had me bring in my guns and he made me glasses. Every 4-6 months was a new lens. He'd make sure the lens kept me focused on the front sight. As the blur got worse for the distant targets I added a merit adjustable aperture to sharpen the target in my sight picture as I focused on the front sight. As my sight got worse and the astigmatism came to be, I changed to a Knobloch setup with a larger lens and aperture with eye blind for the non-sighting eye. About that time I was shooting at 100, 200 and 500 yard matches. One day at a rimfire match I started to shoot turkeys at 75 meters and I saw 3 turkeys where there should only be 1. I shot at the middle turkey and missed. Next set of 3, I shot at the left turkey and missed. Next set of 3, I missed the right. I set my gun aside and waited for the line to be called. There's too many scopes out there to worry about what my lying eyes are tell me. Other than I got old and it's time to move on. Put a scope on it and see perfectly clear.
I do shoot pistols with irons but that's at 50 yards max and it better be at least 10" across. I'm actually getting ready to use a red dot and a reflex sight.