Common guys...he's talking about a 22
Magnum...
not a 22LR.
Huge difference. The 22 Magnum uses a copper-jacketed 40gr slug at roughly 2000fps. And they make an even higher velocity load these days, employing a special lighter bullet. The OP stated it was his
most-used round, not that it was neccessarily the "best" round.
Some 35 yrs ago, I used to own a Savage bolt-action 22 Magnum when I was a youngster. Pretty punchy for a 22 rimfire. I'd say it would be fine for up to coyote-sized game, as long as the range didn't exceed 100 yards or so. No, it would not be fine for a moose, or any other big game, but I don't think that scenario was implied.
That said, I can remember when I was about 10yrs old (circa 1958): we had recieved a phone call from my uncle (who lived about one mile away), for all of us to come over right away and "see something"
When we got over there, I was just totally amazed to see this huge dead
black bear hanging in my uncles garage. It had been raiding his garden. So he shot it. With a 22.
A 22LR....
eight shots. My uncle said it dropped instantly on the first shot, but the 7 others were for "just in case". He said his first shot was in "the ear", so the little slug apparently had entered the brain.

So...why did he use a 22? I don't know...I never asked him. I do know (for a fact) that he also owned a 12ga shotgun, and a Winchester 30-06. Either would have been WAY more suitable...
Bud