You used to be able to buy CB and BB caps - shorter then 22 shorts - I don't really know what's out there now as I pretty much stick to LR now. When I was a kid - late 50s/early 60 - we bought CB caps to shoot gophers with. For squirrels - we used 22 shorts as my Dad was concerned about the distance they would go. A brick of shorts back then was $5.00 a brick (500 cartridges) at our local hardware store.
If a pair of '51 Navies were good enough for Billy Hickok, then a single Navy on my right hip is good enough for me . . . besides . . . I'm probably only half as good as he was anyways. Hiram's Rangers Badge #63