A year or two before I retired I had Lasik eye surgery so I don't have any problem seeing 100 yds, or even 500 or 1000 yds.

A couple of years ago I thought I needed another Model 94 Winchester and bought one off Gunbroker. When I got it home, I sighted it on a rock a hundred yds or so on the hill above my house. I could see the rock perfectly, but the iron sights on my new .30-30 were just a blur.

I've since found that if I wear low power reading glasses I can focus on the iron sights of that .30-30 or my pistols, but then the target is a blur. Out to 100 yds, if my target is large enough, I can hold on the center of the blur and usually hit the target.