For many years I enjoyed Squirrel hunting with a .22 rifle. Quite by accident, I learned way back I did not want to use Hi-Velocity shells.
I have many times sat under a Hickory/Beech/Oak tree with a passel of Squirrels working it & firing at one would not even stop the others from feeding when using standard velocity loads. Under the same situation, ONE Hi-Velocity shot would Clear the Tree.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra