.22 rim fire will only annoy a griz.
Maybe if you hit it in the eye just right, or down the ear hole, but you’re going to need better plan...and a much big weapon.
“.22 rim fire will only annoy a griz.”
Much depends on the size of the grizzly, as well as shot placement.
There have now been two stories about adolescent grizzlys killed or mortally wounded with a .22 to the gut.
There are a few incidents (I recall three) where adult grizzlys have been killed with .22 rimfire with head shots. One is Bella Twin in B.C., with a shot to the temple. She followed up with multiple shots to the head at close range when the bear went down. She was using .22 longs.
Another was a prospector walking on the tundra with his dog. The bear and dog got into it and he only had a .22 single shot and a box of shorts. He just kept shooting. Eventually, he got a lucky shot in the bear’s open mouth, through the roof of the mouth, into the brain. It was likely a smallish adult, given where the incident occurred.
The third was on Kodiak island, where a couple of teenagers suprised a brownie (we now know that they are just overfed grizzlys) that stood up right in front of them, on its hind feet. One fired one shot from the .22. It went in under the chin and into the brain, killing the bear.
I would not pick a .22 as a bear gun, but if it was what I had, I would not hesitate to use it in an extreme situation.