Most Helpful Guy
This guy sounds like a creep. I know I have issues telling my ex off if she does something bad, but this is just horrible.
If you've moved on, or are trying to, he should be giving you the space you need to grow as a person, not aim a gun at your new boyfriend.
Call the police and be happy with this new guy. Even if you felt like you had a great relationship with this old guy in the past, he doesn't like sound he's worth losing this new fellow over. There's a 99.99% guarantee that you won't regret it, even if that means going through the court system. You deserve to be happy, and you shouldn't let your ex, who clearly doesn't know what he wants, to drag you down with him.