I have no first hand knowledge of stopping a bear charge.
I have and a 130 grain Nolser stopped it all.I would want nothing less and I also have been gassed several times and was taught how to work through it to take care of the matter at hand without a mask.
Life or death situation and someone prefers a spray over a bullet provided he or she is capable of making a good shot under the stress of the event?
Why not hair spray and a match or a flame thrower?
Because if there that close, you already lost!
Jayco