I carry my J-frames in either 38 special or 357 - the latter with an oversized rubber grip. But the only time I’ve pulled a gun in self-defense, it was my 22 LR. I had it with me for plinking purposes out hiking a long way from civilization. When I returned to my car, 8 guys were drinking whiskey while sitting on my car. As I got closer, they got off and started to spread out.
I pulled my 22 LR and held it at low-ready. If they rushed me, I’d have raised and fired in one motion, as I normally do when practicing. But...no one asked me the caliber. No one cared that I had 6 rounds to 8 of them. No one shouted, “8-6=2, let’s get him!”
They just stopped trying to surround me. I struggled to get my keys out of my right pocket with my left hand, then got in and started the car without putting my revolver away. Then drove off - and have spent the last 40 years carrying my car keys in my LEFT front pocket.
Even a 22 LR in the face can be devastating. Or the chest.
“Reagan was seriously wounded by a .22 Long Rifle bullet that ricocheted off the side of the presidential limousine and hit him in the left underarm, breaking a rib, puncturing a lung, and causing serious internal bleeding. He was close to death upon arrival at George Washington University Hospital but was stabilized in the emergency room...” - Wiki
And of course, a 44 magnum round might go thru muscle tissue and do nothing serious.
So I PREFER to carry my 357, or at least my 38 special. But a 22 of any size isn’t without some self-defense potential. Heck, all things being equal, I’d prefer to be carrying my Model 29 loaded with high power 44 specials...but all things aren’t equal.
I’ve considered getting one of the 12 oz J-frames in 22 as an easy to carry and accurate to shoot little revolver. Kind of expensive though and probably not as good as the Ruger LCP I already own.
The .22 mag is probably a nice carry for hiking. I’d have to check the Model but S&W makes one with a slightly longer barrel, Model 41 or something. I keep putting off getting a nice holster for mine. When I researched it they called it a rat gun.
I carry a S&W Airweight .38 snubnose in a DeSantis pocket holster in my right front pocket. My keys and wallet are always in my left front pocket. Only had to use mine once to shoot a pitbull that had my corgi by the back of the neck trying to shake him to death. With my left hand holding onto my dog's leash I was able to draw the .38 from my right pocket with my right hand and shoot the dog twice. No need to rack the slide and no danger of accidentally shooting myself.
Several years ago I spoke with a young man from Mexico who had seen the results of a good number of shootings. I asked him if a .22 cartridge was effective for self defense. He answered that the few .22 victims he knew of that had survived wished that they hadn’t.