They were made by CIL. Some places sold them for a little bit more than regular 22s.
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Sweeps General Store“Whew! The new 22 ‘Whiz Bangs’ are in! Holy! 49 cents a box...” And Mike’s face dropped. I could sympathize. Geez, 49 cents for a box of rimfire cartridges! Who could afford that?
Back in those days, you could feed your 22 Cooey for 39 cents a box of fifty. Being kids though, we rarely had 39 cents. But Old Man Sweep was a businessman and would sell them one cartridge at a time for one cent each. High style at five for a nickel!