Help with multistage balloon-tipped water missile

I'm designing the perfect water weapon of mass soakage-the super water missile, and I'm shifting my attention to multistage water rocket thrust systems. My finished product will hopefully be able to reach high altitudes, acheive moderate horizontal distance, and either drop many water balloons over a specified target area, or be tipped with a very large water balloon for a "wet impact" (very wet). I don't know how multistage water rockets operate though, and there are no instructables on how to build them. I searched Google, and all I got was pictures. No DIY's, how-to's, or tutorials. Could anyone tell me (or better yet-show me) how to make a multistage water rocket-or at least how they operate?

Well this is about a year since you created the post, but seeing what you are thinkingn of i might have an idea, first you have to have a water rocket aluncher, you can get a cheap 40 dollar one from pitsco.com, multistage might not work but what you can do is that you need 2 or 3 2 liter bottle, probably 2. As a brief statement it would probably work as a mortar or artillery and you'd haven to figure out from your own experience distance and power. The first bottle would be the launching bottle connected to the platform, then you take the second bottle and you cut off the top of it, so you have about the lower 2/3rds of the bottle, you can just stick it on there and it will stay. Then you might want to consider sanding the edges, i've done this before about 15 launches or so with water balloons, you put 1 water balloon for about 150 foot plus distance,( depends on how you aim.) Or 2 balloons i've tried at the most and make it that it launches 50+ range. But the only problem is being sued. Because if you launch a small waterbaloon straight up, it almost breaks the line of sight, and when it hit the ground. All that was left was mud and some grass in a short 4 inch radius,( about twice the size of the waterballon. As for multistage, you have to figure out a system where the bottle are connected loosely,( more than 2, maybe 3, 3's heavy by it's self.) That each segment has it's own ballon.I''ve seen from one of your other instructables, thatn you have an air cannon, if you pump an aircannon up to 100 and shoot a ordinary 2 liter bottle. it gets tons of distance height. so from there, you could go,(being painful), a water balloon rpg style weapon. But if you really wanted it to say, drop water balloons over a distance or airstrike the target, i don't think that would be possible with a single rocket. If you find a way to put two two liter bottle together, and increase the power, than most of this would be possible.