Most of the emphasis here and in other forums is on two-legged threats against a CCW, the muggers, robbers, rapists, etc. Sometimes the threat can be in the form of a dog.
Just a few days ago, a 60-year-old woman, walking for exercise near a senior center in North Merrick NY, perhaps a 15 minute drive from my home, was set upon and severely mauled by two pitbulls. It seems, that at least twice yearly I hear or read about someone mauled by a pair of pitbulls somewhere in Metropolitan NY. Pitbulls are especially prevalent in high crime areas and they seemingly always attack in pairs, indicating that they must belong to somebody.
In this incident, arriving police officers shot and killed one dog but the other escaped and is being sought. In selecting self-defense calibers, most any will do just fine against a dog. However, I'd think twice about using anything less than a .380 ACP. I've never shot a pitbull and I hope I never do but it's my understanding that they are not easily put down unless the brain or spinal column is struck.
If you have had to defend yourself against a dog(s) out to re-arrange your body parts, share your experience with us. We may learn something valuable.
Int'l Assoc. of Law Enforcement Firearms Instructors