While I don't have grizzlies, I do have far too many bears around our cabin.
I tend to stick with a 12 gauge with buckshot, slug, buckshot, slug, slug slug.
My reasoning, especially in summer with thick vegetation, I would hope the buckshot would spread out more because I may not have a lot of time to get fully centered up on target. Especially if he's charging.
By the 2nd shot (slug) , I would hope that I would be squared up and on target and able to put the 1 oz slug somewhere on it better.
I have patterned the gun and know that the modified choke I keep in it will keep most of the pellets on a disposable plate at almost 20 yards. Considering that bears are a lot larger than a paper plate, I'm not all that worried about having a bunch of pellets not connecting with fur somewhere. I'd be fine with a wall of buck, but realistically, a 16 inch spread at 25-30 yards is still likely going to connect with something. Hopefully if not, the slug will fly more true.
