My bear spray comes in the form of 240 grain sleeping pills, fed from my darling .44 mag.
After the gentleman last year got seriously mauled AFTER emptying his bear spray on a grizzly, I won't take any chances. A charging bear shouldn't be deterred, it needs to be stopped.
Check this link out, but note in advance there's a hefty bit of blood on this guy:
https://www.youtube.com/watch?v=tK609rbSBLs