Here in Alabama, poachers take deer at 100 yards all the time. The report is quiet enough that most people can't detect direction 1/2 mile or so, and usually the poachers are spotlighting so they just aim for the eyes. The game wardens catch a few every year, but there are so many that it is still fairly common.
So is the 22lr enough to be humane at 100 yards. YES.
