When I was a kid I used a red ryder also, those things never had a lot of power, but it was enough to take down a carpenter bee , I got fairly decent at hitting them too, haven't tried it since then, but I'll have to check this salt gun out !
I just saw the price of those CCI .22 long rifle shotshells was something like $10 for a box of 20.
That's expensive !!!
I wonder if you could make your own insect-killing shotshells for a revolver or single-shot .22 rifle by using a .22 blank nail-propelling cartridge (from the hardware store) and putting a small amount of salt, rice, cat litter (clay), or just clean pool filter sand between a few bits of tissue paper as wadding. One wad between the blank round and the "shot charge," and the other on top of it to keep it from falling out the muzzle as you handle or aim the gun.
I might not want to blast sand down the barrel of some of my rimfire guns, but I have a well-worn Ruger 10/22 barrel that I replaced with an aftermarket match barrel years ago. I wouldn't mind scratching that bore up a little bit.
If I had one of those Heritage Arms .22 single-action revolvers that only cost about $140 brand new, I'm sure I'd be willing to try to make some homemade insect-killing loads for it, even if the shot payload was abrasive.
I have the bug a salt don’t work as good as an old gamo break barrel pellet gun I have. Take a tiny piece of notebook paper roll it into a ball that will push in like a pellet and close the barrel. I found mixing rock salt and table salt works best. Just put a pinch down the barrel hours of fun and will knock em down close to 10yds. You can also shoot tward the house this way