Jingle bells ...
It's worth pointing out that the National Park Service, the U.S. Fish & Wildlife Service, and the responsible state agencies in all the Western states advocate for use of bear spray as preferable to use of firearms, for the reasons Deb gave in her post above.
Pepper spray has several more things going for it - it emits significant noise when discharged and a large cloud of orange mist, two more things which can serve to stop a charge. Also, the spray is discharged at pretty high velocity ( something like 70 mph sticks in mind, but I won't swear to that ) so it does have some "upwind" range. That doesn't prevent blowback, but is probably one of the reasons so few people report that as a problem using bear spray.
Bear bells may be the subject of jokes, but one personal experience suggests they are worth carrying. Coming back from Grinnel Glacier in Glacier National Park several years ago, some folks who had the opportunity to watch a large grizzly ( they're all large, right ?? ) coming down a slope on a path that would intersect the trail we were on, at about the time we would reach the point of intersection, told us that about the time they heard our bear bells, the grizzly adjusted his direction and headed up the slope away from the trail. They loaned us their binoculars so we could get a better look at the bear - better seeing it that way than when meeting it at a point of intersection.
While in a local fly shop this morning, I listened in while a couple related their experience a few days ago on the Iceberg Lake trail. The woman, in the lead, rounded a turn and was face to face with a momma griz and two cubs. She alerted her husband and then took off running. The bear did not give chase. After she ran by her husband, he more or less stood his ground, sidling away slowly from the bear. She kept on walking down the trail toward them, but eventually lost ground to them and contact with them. They didn't have bear bells nor bear spray. Their experience was probably more typical than the ones you read about that end badly.
Deb made the point about grizzlies being unpredictable. That is the one thing to keep in mind. And the best reason to use bear bells and carry bear spray, and know how to use it and keep it handy.
John
The fish are always right.