Delay Burst Disk Grenade Design - New Pics

[Davidvaini]

So guys, now that I made the Burst Disk cartridge design, I figured I would try hand at a grenade device used for CQB. Now my local field rules are that if a grenade goes off in a room, whatever is in that room is dead.. you can use flower or BBs.

So as some of you may know my Burst Disk cartridge design has a peice of PVC pipe with the foil tape on top.. it then gets pinched air tight by a coupling.

So I decided to make a design that would have an air delay via pin hole.. The main chamber would get inflated via a co2 inflator and slowly leak into the secondary chamber with the burst disk.. as soon as it breaks the air rushes into the cap.. the cap has holes drilled into it so the powder goes in all directions.

[starman]

Is the flour loaded in the top cap or under the burst disk? If in the top cap, what will keep in from leaking out when handling and throwing? If under the burst disk, won't you have fluor sifting into the main chamber through the small hole?

And I would think the small leak hole would need to be very small indeed to get the effect you're looking for. Have you determined this hole size already?

Edit: You will need to make the top cap fit pretty tightly, much more that the burst disk holding power. Otherwise you'll just blow the cap off and not burst the disk.

I like the idea...

[Davidvaini]

the cap idea does work.. it holds on.. its how my burst disk cartridges work. The pipe with the tape is very hard to get off and wont come flying off.. all the air will be redirected out the holes.

and the pin hole will be max 1/16". The flour will go inside the secondary chamber and will not go through the whole because of surface tension.

EDIT: found another Air delay mine.. same sort of concept different way to attach a burst disk and mine has the cap design with the holes in it.

http://www.spudfiles.com/forums/air-del ... t6083.html

So yes the pin hole idea works..

[daberno123]

Seems like a pretty foolproof design. It might take some tweaking of the volume sizes of the interior and exterior chambers to get the delay that you want right.

I guess performance isn't really an issue. It sounds like by your field's rule as long as the thing goes off it counts as a kill.

[Davidvaini]

On my local field performance of these arnt that needed but considering these use burst disks.. im sure the performance will be more than adequate.

[keep_it_real]

you definitely want a smaller hole than 1/16" (I realize you said max at 1/16 but anyway). I tried a similar idea once with about the same size secondary chamber and a 1/16" leak hole. The burst disk broke in half a second. I think it was 2 or 3 layers of aluminum foil in a 1/2" union at somewhere between 60 and 80 psi.

It would be coolest if it was adjustable but that would probably make it too bulky.

[Davidvaini]

yeah im afraid that it will burst really quickly using a co2 inflator. I will vary the size of the hole untill I get it right..

[SP00K]

EDIT: found another Air delay mine.. same sort of concept different way to attach a burst disk and mine has the cap design with the holes in it.

I was about to post that link until i read you had found it.

I made a couple of different mines a while back when I had read that thread.

I had made this mine last saturday and it worked pretty well.

[jimmy101]

You might be able to use a very small needle valve instead of the pinhole. That would let you adjust the delay time.

Need an pretty small valve (or hole) to get a decent delay.

Or, not to safe but ...

Use a Bernzomatic torch head; needle valve (?) plus the hair thin mixer hole at the end of the pipe as the pressure source. Should bleed pretty slowly.

Just don't use it around any ignition sources.

[SP00K]

You might be able to use a very small needle valve instead of the pinhole. That would let you adjust the delay time.

Triggered air bleeding was the only reason I never actually decided to make a grenade. I made a mine because of the possibilty of triggered reaction.

I felt that the grenade was to conspicuous when it came to field use because it wasn't able to be 'charged' and held for whenever you needed to use it.

It's kinda hard to explain what I am talking about, but I'll post pics soon.

Edit: the needle valve is the solution to my answers btw.

[Davidvaini]

Well If i get these to work correctly I will be able to have a grenade in my hand.. quickly attach the co2 inflator.. press the trigger for less than a second and throw/roll it into the other room and then it goes off..

I have another idea to delay the time some more in case I can't get it long enough. My idea is to put the tire valve on the top next to the cap with the holes in it.. That way it needs to go a full 180 degrees to get into the pin hole.

EDIT: Reason I don't want to put the tire valve on the side is because I want to be able to roll these things in cqb.. lessen the damage on the pvc/paintjob and make sure I dont hit anyone directly in the face or something.

[Imortal87]

Dave I think I found the answer to how these can be made and quickly with minimal drilling and even with an adjustable time delay!!!

[Davidvaini]

This is why we make a good team... I come up with an idea.. you improve it.. You come with an Idea.. I improve it.. We improve upon each others work.

Team I.E.D International FTW!
Team name is subject to change without any written warning, please be advise.

[Imortal87]

hey can you hang out today? give me a call

[SP00K]

Well If i get these to work correctly I will be able to have a grenade in my hand.. quickly attach the co2 inflator.. press the trigger for less than a second and throw/roll it into the other room and then it goes off..

Yeah, that's pretty quick now that I think about it. But something about having a 'charged' grenade hanging of a belt loop, it just gets my blood flowin, it makes me need to make one.