Incidentally, for those who think sideshields don't matter...
This past Saturday I was at the range with a group of people. One of the women was wearing prescription glasses with polycarbonate lenses, slightly oversized, but no sideshields. She was also wearing a brimmed hat which was pulled low enough that no brass could enter the top of her glasses.
Nevertheless, a piece of brass came in from the side and lodged behind her glasses. Fortunately she got her eye shut in time, so she only had to deal with a blistered eyelid rather than a blistered eyeball.
It was a safety problem for everyone on the line, too, because as too many people will do when in pain, she forgot all about the loaded gun in her hand as she swung around.
If you're going to wear regular glasses on the range, get sideshields!
pax