You are in the right, but if you don't have a good relationship with your neighbor you are not really winning.
Try to catch him at a time when he is not flipping out. No fire burning (and maybe none the night before). Early enough in the day that he is not drinking. Bring cookies or the equivalent.
Don't tell him you are right. (He knows that, even tho he will not admit it. And it gives you the upper hand in this conversation. Be polite and don't acknowledge that.)
Tell him you care about his needs and you believe it is possible to find something that works for everyone.
Maybe you can move the firepit. Maybe you can have fires on the nights he goes to his rageaholics anonymous meetings, plus one other night. Maybe there is something you would like HIS family to do less of (besides yelling at you) and you can trade. Work something out.
And you don't have to commit. Agree that you will both try out the new arrangement and see how it goes. You will still always have the upper hand.
He's your neighbor. You might need his help someday, or his cooperation. It's not like you are going to be best buds, but you could try to have some level of detente.