The Savage .22 and 410 or 20 gauge over and under shotguns were very common back in the 50s when I grew up. After a short time most of them had broken selectors and no longer worked. They were notorious for failing to work properly. I can't recall ever seeing one that actually worked.
I had a buddy that had the .30/30 20Ga combo with a Weaver Qwik Point on it. It definitely worked as I ate some of the deer it killed.