I have a 12 ga for a house gun. In bear season I keep it loaded with the first 3 rounds slugs and then 3 00-buck. In winter I switch the order.
Leave the buckshot for human targets. In the early 1980’s the Alaska Dept. of Fins and Fur tested buckshot vs. slugs on some brown bear skulls they had that were overflowing their HQ freezer. None of the buckshot rounds penetrated the skull and only about 1/2 the typical round nose slugs did - the others deflected off. Then they tried the then-new to the American market Brenneke slugs. They penetrated 100% of the time due to their sharp-shoulder design. After that “study” was published every LEO and fish cop in the state stoked their 870’s with Brenneke’s. So do I.
Yep, the 12 guage is our bear protection at home. I also carried one while guiding in Alaska. We had a cracker shell as the first round and then slugs after that. Only had to fire the cracker shell once.