I don't like having different kinds of ammunition in your gun under most circumstances. Unless you're super calm, you're going to forget what you've loaded. Under a great deal of stress, all you know is point and shoot. You won't be able to count rounds. As the bear is charging in, you'll be wondering whether you're still shooting the blanks or live rounds.

The other thing, of course, is bear defense. We might as well open up all cans of worms: 9 vs .45, AK vs AR, Mac vs. PC, Lauren Bacall vs. Catherine Deneuve...