Just reread this thread. Re Pepper/OC Spray. The defence grade stuff is very effective to outright no effect at all on people. In fact the more times you experience it the less affect it has. Yep personal experience and that of many workmates. So, to me, it would stand to reason that the same would apply to animals; with this in mind no way in the wide world would I rely on Bear Spray or the spray for use on humans to deter a bear let alone stop it if charging.