SJBenne, are you living with your mother? If so, can you move out of her home to a location that is kept secret from your brother? And probably from your mother too, as she might tell him. There are often inexpensive rooms for rent in the neighborhoods around colleges. I think your first concern needs to be for your own safety. If your brother is blaming you for all of his problems in life, and if he does become murderous, you might be the target. This sounds very serious to me.

This sounds good in theory, but studies have shown that taking out a restraining order on vengeful people can often escalate their violence. They can get super pissed off at the person who took out the restraining order and come after them. This happens all the time, so please beware. Just because it becomes a crime for the person to set foot on your property, it doesn't mean they will obey that and not come after you. The police will not be there, and it will be too late. I'm sorry if that is being too blunt, but it's the truth. Just because you file a restraining order does not mean you will be given 24 hour protection. Last year, a woman was murdered where I work by an ex-boyfriend that she had just taken out a restraining order on. She had moved to a secret location to protect herself from him, but he knew where she worked and he got her there.

SJBenne, I would like to recommend a book to you that covers some of what I wrote above. It can help you predict which people will escalate to violence, and it helps you learn to trust your own fear. The book is:
The Gift of Fear by Gavin De Becker.

Good luck. I hope you will take whatever action you need to in order to protect yourself.