Have you ever wanted to fire a water bottle from a shoulder-mounted launcher? I know I have. This Instructable takes the basic "water bottle rocket" science lesson and expands on it, combining the ability to aim with a convenient trigger mechanism. It can be built in a few hours using parts from a hardware store. But before I continue, here is the requisite disclaimer:

PLEASE, do not aim the Bazooka at people, animals, your neighbour's prize-winning tomato plants, or other objects that may be damaged. Only launch outside. Don't do anything stupid, like lighting the bottle on fire before launching it. Use only water as a propellant. Do not over-pressurize the bottle. Use under adult supervision. Keep small children away (regardless of my video!) Use the thinking part of your brain.

MOST IMPORTANTLY, do try to retrieve every bottle you launch. Let's not litter, okay? I'd also suggest using "reclaimed" water as propellant, such as rainwater, snow melt, or the like.

Step 1: Materials and Tools

Here is a list of materials you will need to build the Water Bottle Bazooka

3-4 feet of 3" diameter ABS pipe
One 3" to 1.5" ABS reduction adapter
One 1.5" to 0.5" ABS threaded pipe adapter
One 1" inside diameter metal washer
About 6" of scrap 2x4
About 6" of 3/4" diameter plastic pipe (any kind)
One #4 rubber stopper, solid core (cork won't work, it has too many holes!)
A bicycle brake lever
Bicycle brake cable housing (cut to fit)
Bicycle brake cable (cut to fit)
A brake cable clamp or similar
Any sort of glue that will adhere plastic to plastic, and wood to plastic

Water bottles - 500mL size, or anything that will fit in the launch tube
Bicycle pump
A long Presta valve - a used bike tire tube is a good place to get one!

And here are some tools that you'll probably need:

Something to cut metal - a Dremel or metal-cutting bandsaw would work best
Something to cut plastic - a handsaw or miter saw or something similar
Something to cut wood - really, any sort of saw would work.
A drill press (or a hand drill, in a pinch)
A sharp utility knife or X-acto knife
Assorted measuring and marking implements
<p>would this be considered a firearm?</p>
Not even a little bit.
<p>It is a firearm. It fires a projectile at rapid velocity. A paint pall fired in the city limits will get you arrested. Shoot you neighbors car with that andi bet you just vandalized it. Check local ordinances before using in city limits. In Idaho It is because it shoots at great initial speed capable of causing personal or property damage. Potato guns and my teen age years come to mind.</p>
<p>My boys big water rocket fans. This might be a grat alternative launch mechanism. have to show it to them.</p>
What if you wrapped the cork with tape?
love the release mecanism. All the ones i tough about are preety hard to build but this is so simple and effective.
I'm building a completly portable water bottle gun and the release is the harder part of it. <br>Because of your instructable i finaly know what to make. Thanks <br>
here's where i'm at so far (it's not finished or fully assembled)
Looks great so far! I'm glad my mechanism was helpful.
Best instructable ever!
My son would love this!
Sounds like a good project for you two to build together! You can get everything you need from a building store and a bike shop.
i wonder if i could put watersoluable paint in it and use if for paint ball instead
Well, if you made a cardboard shell for paintballs with flaps cut into the front, it should work. The flaps will open when the shell is shot, and the paintballs will keep going. As long as there is a tight enough seal and you understand me correctly, it should work.
No, I don't think so. The bottle moves forward, while the water goes backwards. So unless you want to tag yourself or your teammates I don't think it would be such a good idea!
Maby put paintballs on top if the water bottle so that when you launch the water bottle the paintballs come out as well.
yea i agree but ive ben brain storming and mabey with a sheild and shoot it over the enemys heads so it puors out on them? ill work on the idea after midterms
I had a feeling that's what you were thinking. Normally you'd only put about 200mL into the bottle, which isn't very much - the chances of hitting your target would be pretty low. If you want to rain paint on your enemies I'd suggest figuring out a way of firing a few dozen paintballs into the air all at once...
yea like i said though i need time for midterms (yea) : (
fill them with paint like you said, but put the bottle backwards and stop it from moving to propel the paint forward.<br/><br/><sub><sup><sub><sup>or put watery paint in a squirt gun, but that's not nearly as fun.</sup></sub></sup></sub><br/>
Well that's not really a bazooka anymore, it's more like a traditional water gun, or maybe fungus' Christmas Cannon. ;)
he said that look at the small text
you could put a water baloon full of paint on the front of the rocket
aquafina bottles suck and die when used as ammo, use Smart Water, they last forever and get pretty good distance. an aquafina bottle expanded on the second launch attempt and got stuck in the tube, epic fail.
Good to know. Plastic bottles are definitely not all created equal!
I use this for paintball. Just fill the bottle with water and&nbsp;paint from my old saggy balls.
wow kool did it work well?
After lots of modifications yes.
ha funny:)
that doesn't sound wrong at all
No, not in the least.
Oh god, I didn't think before writing that, by &quot;my old saggy balls&quot; I meant bad paint balls.
its all good. i understood your meaning, but i has a dirty mind so i had to point that out XD
same here lolz<br>
Oh god, I didn't think before writing that, by &quot;my old saggy balls&quot; I meant bad paint balls.
well then..........................
ok this is about the best thing i found under rockets idk how u made it or even thought of it but this thing is krazy awesome but the waterbottle dousnt go really far
Thanks! I think it could be made to go farther by adding a nose cone, and launching when it's not -20 celcius outside.
ya a nose cone and some fins would be good
Soda bottle are built to resist more pressure because they have to hold in the carbonation if you use a soda bottle then you could pump it to a hire pressure with out fear of the bottle bursting.
That's true; some soda bottles are quite strong indeed.
The first videos are up! They were taken last night in -20C temps. Just.For.You. I'm about to head out in -13C temps to get a daylight video of the bazooka in action.
Shoot footage from behind! The side shot just lets us know that it launched. A shot from the back shows the trajectory. Much more exciting.
And thanks for freezing yourself for the cause, btw.
I wonder if the low temperature had any effect on the flight of the rocket...
Cool, thanks! I wonder if you weighted them at the bottom/front they would go farther.
I was thinking the same thing. I've noticed the same effect with Nerf ammo. On its own it's too light and it doesn't have enough inertia to counteract the air resistance. Tomorrow (when it's light out again) I'll try a few more shots with a weighted bottle.
Yeah, it looks like a tiny wobble sets it off and then it quickly brakes in the air. We were shooting a foam dart with the christmas cannon first and after we dropped a small weight in the front it flew clear across the office, about 150 ft.

About This Instructable


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Bio: By day, Jeff is the Jack of All Robots at Clearpath Robotics. By night, a mad scientist / hacker / artist / industrial designer wannabe!
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