I just have to comment here: I have been carrying weapons professionally for just short of 46 years now, in all possibe scenarios, military, LE, instructor, contractor etc...
I have always tried to have a shotgun in the mix because they are great for close in work-like HD, or defending a fixed post in heavy cover, or, or, or.
Now to get to ammo. I have seen some truly scary comments above:
1. Birdshot is for the birds, it will leave a large shallow wound which may be disfiguring, but it may not be lethal. Just what you do NOT want, a disfigured wounded felon to sue you later, or to kill you because he was not stopped.
2. Buckshot is designed for animals of medium size, like large deer, now what or who does that sound like? Select the type of buck you feel is good for your situation from #1 on up it will do well. So will slugs, again dependent on you physical layout.
3. NEVER, NEVER mix loads in your magazine. The pros have enough trouble trying to remember what was up first, what is up now and so forth. To the point that virtually ALL military/LE organizations prohibit mixing loads in the mag. Some even prohibit carrying different loads on the person. Some exceptions are made for SWAT or other hyper trained personnel, but even they are prohibited from mixing loads in the mag. Why? Because after any fatal shooting there are 2 legal aftermaths, criminal and civil. The criminal investigation usually dosen't bother anyone whose heart was in the right place. BUT the civil suit will give one fits. You do not want to be saying whay one load was more or less deadly than another, and why you had those loads mixed up in the mag, there is no way you can come out of those questions looking good-and it is the BGs lawyers job to make you look bad.
And for Gods own sake. NEVER use less lethal ammo, or ammo that you may think is less lethal because if it produces a lethal result, your legal goose is cooked-at least at the civil trial. Using less lethal ammo lethally just screams negliegence-which is what the lawyer for the plaintiff wants.
You should not care if the BG is dead or not, as long as he is stopped, but a dead BG is far better for the shootere legally. Only one story, limits on damages in many states, AND you do not have to explain why he was so badly disfigured or maimed for life by your "unique" ammo selection.
