"Use enough gun".

And that is strictly a matter of opinion. Well, mostly.

IIRC, Bell didn't think the .22 Hornet was much of a rhino gun.... smile

That said, I'd carry a .308 without hesitation. My walk-about rifle is a M94 in 30-30.

But size does matter sometimes, and placement matters more. Shooting a rifle one isn't afraid of is a good idea.

The only true cost of having a dog is its death.