...For HD, use your favorite hunting piece with the ammo that you normally hunt with and you will be much safer from prosecution when the DA reviews the case. If you are an uplands hunter, have #6 or 7.5s in the magazine. If you are a clays shooter, have 8s or 9s in the pipe of your favorite shooter. A specialty gun equipped for combat with gadgets all over it loaded with combat loads will almost assure you at the very least a civil action, or at worst a criminal prosecution.
You may take this at face value or I have wasted my time typing this post. I don't like to see people get into trouble because they are stubborn about their beliefs. Remember, I have been through many reviews with the DA. He can ruin your life with the stroke of a pen. I always recommend that there be no prosecution for a burglary or home invasion. That carries some weight but the DA, when he sees the photos of a loaded with buckshot pump gun owned by a quail hunter, lots of visions cross his mind. Visions of glory at issuing a warrant for involuntary manslaughter.
The shotgun blast may not kill your bad guy, but it will put instant brakes on even a drug crazed perp with a heavy coat on. A shotgun blast to a guy with a bullet proof Kevlar vest will knock the breath out of him and leave bruises that you wouldn't want to believe. The Kevlar factory is about 20 miles from my home and they have excellent testing facilities. A shotgun blast at 30 feet is effective with any size shot. No, the shot won't penetrate but it leaves some very nasty bruises. I've read many posts that complain that the perp may be wearing a heavy coat, thus the need for buckshot. Not to worry. Any shotgun blast will change his plans. A shotgun expends its energy on the outside while a rifle projectile expends it's energy inside the body. If a bad guys comes acalling, I don't want to kill him. I just want to protect my home. I'd rather visit him at the ER or the courtroom than to go to his funeral.
Gebtlemen, I am a retired cop that has seen lots of lives ruined by the judicial system in both civil and criminal actions though the homeowner thought he was acting properly. The Castle Doctrine does not protect you if you act outside the confines of reasonableness. That is why I suggest that you have the gun that you use in your normal shooting routines loaded with the ammo you use for that routine. It will save your life if a bad guy visits and a lot of grief when the prosecutor makes a decision on whether to have you arrested.
Not all of you, maybe none of you, will agree me....