I'm stuck always wearing eyeglasses, so eye protection is a "non issue" for me. My normal glasses have polycarbonate lenses, and they'll protect against normal things like powder granules, bouncing brass, etc. But when shooting steel at a match I switch to real prescription safety glasses. Polycarbonate, too, but 50% thicker.
I know of several incidents when eye protection came in handy - once, when I was a kid, lead or jacket metal bounced back from the bullet trap when one of my shooting buddies fired his .41 or .44 magnum in the next shooting lane . . . it came back hard enough to put a small scratch on the tip of my nose before bouncing up off my left eyeglass lens.
Another time, a couple of us went shooting and I insisted the "newbie" wear safety glasses. (I'd brought along an extra pair.) When he fired the other guy's M1927 Thompson a glob of grease, powder, and other schmutz hit him in the face and spattered his glasses. He thanked me.
And once on a trap field I saw a guy's O/U explode. This was one of the most thoroughly destroyed guns I've ever seen, but other than a few scratches on his arm and face, he was uninjured.
These are the only incidents I can recall over many tens of thousands of rounds fired . . . there were probably times when, thanks to glasses, I didn't even notice a "save." But even in the case of the incidents I've mentioned, thanks to the use of safety glasses they'e no more than memories, with no lasting consequences.
The magazine blew out of the bottom, the bolt flew open, the bullet stopped about two inches short of the muzzle and the face of the cartridge had torn off backwards, the brass cylider stuck in the breech. A .22 popping in your face makes a lot of smoke and noise. Got it all cleaned up and threw away the damaged magazine.
