Airburst Paint Grenades

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Zippster
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Mon Dec 08, 2008 10:39 pm

You read the title, and you know why you're reading this.


If you don't know what a paint grenade is, its nothing explosive. These 'grenades' are merely small sections of surgical tubing with one end tied off which are filled with some paint-like substance of your choice and sealed by a washer, coupling, or other such device to hold the open end pinched shut until an impact knocks it loose. Normally to use one you pull out the hopefully existent safety pin, loosen up the washer or washer-substitute, and lob it at whatever you want to mark-up, and upon hitting something the washer pops off, leaving the surgical tubing to spin like crazy and spray whatever you filled it with everywhere. Its a good, cheap, and for-the-most-part effective and ultimately safe grenade, without any rule-breaking explosives or expensive bb-costs. However, these devices are severely limited by their finickiness of triggering and achieving of the desired spinning effect, and more than once have I thrown one just to have it pop.


Seeing as BBMG's cover the heavy direct-fire aspect of our home-built airsoft arsenals more than adequately, I've been pondering indirect artillery-support, and I've come up with this. Introducing the Airburst Paint Grenade, or APG for that comfortably familiar explosives zing. Instead of being limited to hard surfaces to trigger paint grenades and that inevitable risk of hitting a person directly, I implemented an anchored ripcord much like SEAKING's airburst design which will at a certain distance yank off that washer and send an alive and spraying grenade over the heads of your adversaries. So far I've successfully tested the concept by tying off the end of the string to a tree and throwing the grenade, so I've taken the liberty of consolidating the ammo and the cord in a removable shell. I've yet to actually build the cannon to accept the shells and fire one for real, but the concept is sound and I see no reason why it won't work.



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Here's the whole shell, and my dog. The side with the oh-so-aesthetically-pleasing electrical tape is the muzzle, and the other side will have the threading to use in a cannon. I didn't want any seams in the inner barrel to interfere with the fragile nature of the grenades so I ditched an attached barrel altogether, and will for now settle with threading each shell on and off - its not as though that takes that long either.


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This is a grenade filled with water which for now works for testing.


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Heres the lockwasher I'm using as the release and the end of the string tied to it. The paperclip is a safety which I will remove before loading the shell.


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This is the shell from down the muzzle, notice the string down to the grenade.


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The front end of the shell, with the rubberband holding on the cord until its ready to fire. Ideally it should unwind nice and neatly off of the pipe until the tape rips the washer off.


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Finally the back of the shell, where I will attack the coupler to the cannon.



This is a work in progress and by no means fully-exploited in any way, so expect an actual cannon to fire these things to come your way. Feel free to copy and expand upon this all you want, I just like the military feel of the word "AGP".


Edit 12/08 - Grammar

Updates will follow.
Proud to be the only kid on my robotics team with pneumatics experience.
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Lentamentalisk
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Mon Dec 08, 2008 10:52 pm

That looks quite possible, though it seems like it would be better just to lob them, holding on to their string, as that way you could control more accurately where they go, or throw them normally if the situation requires it.
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Zippster
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Mon Dec 08, 2008 11:08 pm

Lentamentalisk wrote:That looks quite possible, though it seems like it would be better just to lob them, holding on to their string, as that way you could control more accurately where they go, or throw them normally if the situation requires it.
Yes but then you don't get the cool factor of having a really loud and hand cannon to launch these things really far and scare the hell out of your opposition. After all, at least half of its effectiveness will undoubtedly come from the sheer intimidation factor of having a miniature bazooka fired at you.


I just thought of the potential for Davidviani's (I hope I spelled that right) burst disk cartridges for something like these, especially with that panzershrek of his... *drool*
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Insomniac
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Mon Dec 08, 2008 11:50 pm

While this may not be all that practical, I think a way cooler alternative to the ripcord is to instead use a parachute on a short bit of cord. If you wrapped it tight enough, the shell would fly out trailing the tiny folded up chute, and after a certain distance the chute would unravel and hopefully snap open very suddenly due to the airspeed. That would jerk on the string, allowing the grenade to continue on while spraying paint.

Not sure how well it would work, but it sure would look cool.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

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Hubb
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Tue Dec 09, 2008 8:29 am

This is very possible, and has been done. I've built one similar, except, instead of using it to lob paint grenades across a field, I implemented a landmine devise, making a "Bouncing Betty" type.

Also, it seems that you got a good head on your shoulders when it comes to this. Send me a PM, and I'll send you some great stuff :wink:
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john bunsenburner
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Tue Dec 09, 2008 9:57 am

What i enjoy is taking those plastic eggs(the ones in two halfs) then i fill it with baking soda(one half) and a vinigar and paint mixture in the othe half. I take 3-5layers of toilet paper and pt it in between. Then i close the two half(You usually have to push really hard). The grenade Is then quickly loaded and shot out of the cannon. If you shoot far eanoth the pressure will build up and stincking paint rains down, an alternative is to use 1/2 baking soda and 1/2 flour, then the paint and vinigar mix. The flour and vinigar/paint make a sticky smelly mixture which rains down on you opponent.
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SP00K
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Tue Dec 09, 2008 10:17 am

This is was one of the first things I did when I first learned about making homemade paintball grenades (not the airbursting effect, the cannon). My first design was a mortar which used a burst disk design where the grenade would be launched as soon as it hit the disk just like a real mortar.

I would love to add this string design to my mortar if you don't mind me borrowing your idea. :P
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Lentamentalisk
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Tue Dec 09, 2008 11:01 am

The string on the barrel is in no way his new idea
http://www.spudfiles.com/forums/back-in ... 14052.html
http://www.spudfiles.com/forums/v-a-l-p ... 14702.html
http://www.spudfiles.com/forums/trident ... -t119.html
http://www.spudfiles.com/forums/antenna ... -t120.html

Someone else also used the string idea here for air burst, but I can't find the page right now, I'm off to school.
Do not look back, and grieve over the past, for it is gone;
Do not be troubled about the future, for it has not yet come;
Live life in the present, and make it so beautiful that it will be worth remembering.
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Zippster
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Tue Dec 09, 2008 11:24 pm

I threw together a mini-launcher with a 3/4" diaphragm QEV, a foot of 2" chamber, the barrel shown above, and a check valve as a hammer and it was immediately evident that to do this you need a lot more power than that. The string burst though works like a charm if you can actually get the grenade out the whole distance. Ideally it triggers just before your target so it is already spraying when it goes over their heads, as the momentum will carry it a little ways until its physics are mucked up what with the spinning and the spraying and the GLOIVEN!!1! loss of mass...

Simpsons Dr. Frink anyone?

I'd love to see how you guys have used this concept before and any and all experience with launching homemade paint grenades mucho welcome. I really want my contraptions to somehow be practical in my airsoft games with my friends, even stationary artillery emplacements and especially something like a mortar. I tried the easter egg and they either pop immediately or not at all, but I'm not giving up yet.

The APG will yet live! (and subsequently own people)
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Insomniac
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Wed Dec 10, 2008 12:01 am

Would you mind trying my idea in my first post? I'd love to see if it works or not.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
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Zippster
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Thu Dec 11, 2008 11:39 pm

Insomniac wrote:Would you mind trying my idea in my first post? I'd love to see if it works or not.
I don't know how soon I can get around to it and I'll have to search my closet for one of them oldschool plastic paratroopers, but I'll give it a shot. Honestly though, I've had bad luck with parachutes deploying in the first place, let alone creating enough drag to trigger the grenade - and even if it does create enough all that force is slowing the flight of the projectile and ultimately decreasing your range.

Still, the coolness factor would be worth it tho 8)


A couple more minor setbacks today, as yet another PVC chamber succumbs to snapped off fittings. I've gone through more plastic parts this week than I have in six months. Must be the Texas winter chill :roll:. Anyways I've gotten around to modding a QEV Brian-style to fill from the chamber and its something that I'd recommend for everyone to really get more fun out of their QEV's. I spent a whole 10 minutes just blasting stuff with air bursts in rapid succession and watching what happens (my dog now rightfully fears this cannon). I might even ask for a CO2 rig for Christmas should it work out that way, which could add some fun to my airsofting :wink:


By my next post I'll hopefully have a working cannon to lob these things for their true power, so until then, adios.
Proud to be the only kid on my robotics team with pneumatics experience.
SEAKING9006
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Fri Dec 12, 2008 7:18 pm

Happy to see my design used in others cannons. I've thought about artillery, but the thing that always puzzled me was how the hell would I get a string to become taught with a ballistic trajectory. I decided that the best way so far is to simply fire something that won't have too much of an impact force and make helmets mandatory. Not the most elegant solution, but the only one I have so far. Cable-pulled air bursts are only effective in direct-fire mode. I (literally) just came up with a few improvements to a direct-fire air burst that involves using a 2X magnification telescope sight, a heavy warhead with low velocity, and a spring-loaded stick to pin the string triggering the shell. The low velocity means it needs to stay almost 'aloft', so I just came up with the idea of using springy 'wings' made of Mylar (or comparable material) to keep it in the air longer at a lower velocity, so the gunner can better time the burst.

In any capacity, indirect-fire is a tricky business. Hence, BTL Industries (my 'company', and new forum name if PCGUY ever answers the PMs.... :roll: ) has decided instead to pursue R/C air support in lieu of artillery strikes. More info on those projects as they develop.
Completed projects:
CA1 SMSS Basic Inline
CA3 PDAB Airburst Cannon

Current Project: Bolt action rifle (25x140mm + 1in shot)
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