I don't understand why people even have damage on in a roleplay.
Well, there are certain times when you want to kill another person legitemitely as part of the role-play, and shooting them and having them die is the best way for it to work.
When I have roleplays, people don't recieve weapons. You don't get a weapon unless you're given it. All Weapons are hidden away, usually in Admin-only or ID-only rooms.
This means no-one gets any weapons, and if someone needs a weapon for the roleplay, they can ask to grab one. Of course, they'll have to have a bit of credibility on the server before they're given them.
(By which I mean, they'd have to have joined in with the Rp for a bit. Obviously someone joining (Regardless of having joined before or not) and immediately asking for a weapon and claiming it for the roleplay wouldn't recieve it.)
If anything, the main problem with this that I have, is if someone either gets hurt by a roleplayer legitemitely using a gun by accident, or perhaps they get over-involved in the Roleplay and wish to attack the Bad-guy, or even they've just decided to do it on their own accord, is that people like to use Hammers. Hammers are annoying because you can hit someone a lot of times quickly with them and do some damage pretty fast, by which time it's too late to hit back with another Hammer. It's still as difficult to move away from them and use a weapon (If you have one).
On my friends servers, where this problem has happened, we've tried different methods of stopping it, ranging from insta-bans to removing Hammers. (Which can lead to it's own problems, especially when the alternative was a wand... which led to constant destruction of peoples work by accident, and then people just like to flick each other up in the air)
Because of this, if someone is Hammering a person, I first use /Forcekill to stop them from harming anyone else or finishing off their attack, then I give a verbal warning about it. Just one. And it doesn't just go for that person, it's everyone else in the server. If someone is there when someone else is warned, then an hour later, they start-hammer killing, they face the consequences as they saw the warning themselves.
After the warning, anyone who has heard it (By which it's simply being on the server for) and then continues to/decides to Hammer-kill ends up being Banned. Not Usually a perma-ban, they're usually short bans, but they do become Permas if they come back and repeatedly break the rules.
The main problem I can obviously see with your stuff, is the whole "Army RPG" aspect of it.
I'd suggest that you put these sort of people into a Team-Deathmatch, all on the same team. It may seem annoying, what with the scores on the bottom, but so long as you have friendly-fire off and that sort of thing, you're not going to end up with these people killing each other. If they start getting stupid and violent, hitting and shooting each-other regardless of it not having an effect on the other person, issue a warning and then follow it up with a punishment if it continues.
That's about the only thing I can think of that would work, IMO.
