When I was in Idaho on an Elk hunt in 98 I went into a small rural Sporting goods store.
I was looking at the used guns and ask the owner if he had any .22 mags, he said no I wish I had a hundred but I can't keep them in stock.
After asking why they were so popular, he heitated then began explaining that they were the gun of choice for bow hunters.
He said the locals would stash one inthe area they were bow hunting,then go to that area during the rut and call up the big bulls and pop one in the neck with the .22 mag. stash the mag, then quarter it and pack it out and no one was the wiser.
He said that in that area at least 90% of the big bull archery klls were taken that way.
When I ask how effective a neck shot on an elk was, he said that if you knew where to stoot one,slightly behind the ear, that they would drop in their tracks paralized from the neck bone hit,then,if necessary, they were finished off with an arrow.
The reasons he gave for using the .22 mag was, they are cheap and can be left out in the weather for weeks and if they get rusted it was no big deal plus the report when fired could not be heard very far.

So I guess if anyone has a .22 mag that they no longer want, there is a little gun shop near Avery Idaho that would love to buy it!