These aren't packs of feral chihuahuas we're talking about, the adult (american) grey wolf mean weight is 88 Lbs, they can weigh up to 180. Imagine an animal almost as large as you, who's very purpose for existence is to predate mammals much larger than itself. Now imagine being surrounded by 20 of them and aware of the fact they have evolved to hunt cooperatively, to take down ungulates that can weight 5-10 times what they do. You are going to maybe get 1, 2 (if god himself intervenes) shots off with your bolt action 30-06 before they swarm you and literally tear you to pieces. If you had your back to a cliff and a M134 Minigun, you might have a chance. Luckily they mostly choose not to hunt humans, but it ain't because they wouldn't be successful. They just have easier prey most of the time.