I'll say it again, I would take the 7mm. They have big teeth and claws. The last thing you want is having to track and wounded bear in the brush, whether it's a black bear or a grizzly, they can both be dangerous. I can't remember where I heard this or whether it's true, but I heard that black bears kill more people every year than grizzly or browns.
If you use the 30-30, I would stick with the hornady bullets. You will get better performance and accuracy out of them. In the 7mm, the accubonds will work just fine.