Wine Bottle Cone Charge

[green beret]

I hope this is in the right section.

Well, I am making a wine bottle cone charge, as described in the Improvised Munitions Handbook.

I have cut the bottle by using the burning string, and I have noticed some cracking in the bottle, down one side and on the bottom, the one on the side is not really of any concern, but the one on the bottom may be. It is about 5mm from the edge of the bottle. So I'm not too sure whether or not this will matter.

I have placed the bottle in a section of heavy cardboard tube, as the cracks on the side have slightly weakened the bottle, and also the tube stops the rough eges at the top cutting up my hand. I am going to leave this tube in place, then put the completed charge into a paint tin with sand around the charge (obviously not in the cone cavity), then put the standoff legs on the paint tin. Would it be worthwhile to cut a hole under the cone so as it dosent have to cut through the tin? Also I am using ANNM with approximately 1.5 grams of AP as the detonator. I know ANNM isn't an ideal explosive for shaped charges, but its the only explosive with a high enough VoD that I have right now.

For the witness plate, I am going to use a thick steel plate, (for Aussies, it is one of those plates that are on those deep telstra pits with the four heavy steel plates) which I will borrow ;) and depending on where I do it, I might have a concrete slab underneath.

I should be able to get some pictures, which I will upload to the FTP, but it is doubtfull that I will get a video. I am not sure when I will do this, I will most likely have to find a new site, almost out of hearing range of houses, things are a little "tense" around here, not all my doing though, someone blew up a porta loo with an "incendiary device" (?!?) and a nearby resident called 000 and said there were explosions going off. Apparently it was heard 1.5km away, and when the fire brigade got there, it was almost totaly destroyed, and some bits were on fire.

Sorry, Ive strayed off :p

So basically my queries are; Will the crack on the bottom matter, and should I cut a hole in the tin under the charge.

Thanks in advance.

[DBSP]

I don't belive that the crack will have any effect as long as it's not the cone itself which is cracked(thats what I belive at least, If I'm wrong I hope someone can correct me).
And scince you've put the bottle in a thick cardboard tube the one on the side won't have any effect either.

I don't think that it is necesary to cut a hole in the tin scince I assume that isn't very thick. Many rockets have the SC placed in the middel of the body and the jet has to penatrate some of the rocket itself before it reaches it's target. That is a real Jet though.

Edit: I just remembered I forgot to tell you that if you want to cut wine bottles, use an angle grinder. Just put the grinder against the bottle and spin the bottle, there is no need to push it hard against the bottle just let it gently tuch the bottle and it will snap by itself after a while, if not just tap it lightly with a hammer on the throat of the bottle.

I have cut bottles with this method that have gotten allmost clear edges afterwords.

[green beret]

Good, thanks for that info, I wasnt sure if the paint tin would deform the jet as it was very close to the cone cavity, and the standoff is supposed to be 3-4 inches. Its not an awfully big cavity anyhow, so I'm not expecting brilliant results. I'll give the angle grinder method a go on the next bottle, I have a few more with bigger cones.

Also, if anyone is looking for suitable bottles for these charges, dont bother checking the cheap wines, hardly any have decent cones. This is because the expensive wines (being of higher quality) use the high cones to seperate the sediment in the wine while they are sitting, resulting in a better flavour in the wine.:rolleyes:

So thanks DBSP I'll keep progressing, all I need to do now is dry the AN, measure out the NM and make some AP, I'll be trying to keep the detonator as short as possible too, so the shockwave travels from the top downward as much as possible and not from the centre out.

Cheers.

[zaibatsu]

Don't forget some of the nice champagnes also have quite substantial cones.

[kingspaz]

or you could cut it better using that toothbrush contraption somebody described in the glass cutting thread.

http://www.roguesci.org/theforum/showthread.php?s=&threadid=2757

that should result in less cracks of the bottle.

[nbk2000]

I would cut away any metal from the bottom of the tin that'd be in the way of the jet formation.

Since you're using a low energy explosive and a crappy liner material, there's no need to make things any more difficult by obstructing the jets formation at such an early stage.

I've used triangle needle files to etch a line around bottles, prior to tapping them on the line with a nail to crack it.

[Cyclonite]

In the future I suggest you make you shaped charge from sheetmetal with a thin copper cone. The cone shouldnt be too deep though, one of the ones used in EOD is about the size of a soup can with a 3" standoff, its handpacked with C4. I dont know offhand the depth of the cone but it does extend approximently 1.5" into the can. Make sure you prime from the top. Oh and cracks in the glass wont matter much, the explosive just needs to be formed the the right shape and have a liner in the cone. I would remove the metal sheet you refered to if you want max. effect. If wont interfere with the formation of the jet much at all if any.

[Mr Cool]

A good way to cut glass is with a long bit of nichrome and a battery (thickness of wire and size of battery dictated by what you are trying to cut). It's the same idea as the burning string method, except that the heating is much more localised to where you want it, and you can control how hot it is for how long.

[Cyclonite]

I had a friend that worked at a place that cut sheets of glass into specified shapes, he relocated a glass cutter. Its like a pencil with some sort of diamond composite at the end. I dont know the price of one but if you plan on doing similar projects that cutting of glass is evolved is works very well, you just trace the area to be cut then tap it with a small hammer or something similar.

[green beret]

Thanks everyone, I'll let you know how it goes, I think next time I'll try using a cone made from an aluminium can, or, as was said, a copper liner. With aluminium, would a coke can be thick enough to form a big enough jet?
Cheers.

[DBSP]

I doubt that an aluminum can(coke can?) will be thick enaugh. And I don't think you can make a good enaugh cone from that thin sheating to be able to use it as a jet forming SC, it would rather just like the glass add a cavity to the charge, it would allso add some shrapnell of course but scince the sheeting is so light and thin I doubt the shrapnell would do any serious damage to the target.

I made an SC with sheeting from a tincan last new years. I used APAN as the explosive. It blew a hole through the 2 layers of 1mm steel plates, the plates where spaced 1.5cm apart. The hole was just as large as the width of the cone and the hole area beneath the charge was covered with craters from fragments of the cone. I haven't got an FTP at the moment so I can't give you any pics of it right now.

[Cyclonite]

The liner does not need to be thick to produce a jet effect, try copper sheet about the same thickness as a coke can. It should work fine as long as you have the right standoff, cone angle and last but not least a suitable explosive the more brisance the better.

Please post experiment results, I havent used anything other than C4 in shapecharges. It would be nice to have my AN based explosive velocity doubts lifted.

[DBSP]

I didn't say it doesn't work with a thin linear, but good luck pulling it off as a pure hobbyist since the tollenranses when using thin sheeting are close to zero. And you have to be very good at soldering to be able to make a perfect cone. To the other difficulties you can add pressing the explosives into the SC without any voids at the same time as keeping the density uniform.

Most people here haven't got any explosive more powerful than ANNM thus that is what will be used.

If you used a copper sheet of about a mm in thickness it's easier to solder allthough more difficult to bend into perfect shape. It will allso be easier to press the explosive into the SC since the cone doesn't bend as easy as a cone made with sheeting about the same thickness as the material in coke cans.

But if you can pull it off I'll gladly have a look at the pictures you will take of your SC and especially your C4.

ANNM workes in SCs, at least LSCs, and I've got pictures to proove it!

[Mr Cool]

I'd much rather use amine-sensitised NM than ANNM in a SC. No problems with loading, constant density, no voids...
I know it'd be considerably more expensive, but then if it doesn't work you know the failure was due to your cone, rather than a huge air bubble that might have been in your ANNM.
Then, once you know that your cones are working, you can try with ANNM if you like.

[Cyclonite]

I think I have some pictures of some shots I did, I will try and find them.
I used military C4 and the molding were pre-made, just stuff with C4,
prime and boom. I lack experience with homemade SC, Iv only used the ones
in EOD. I guess the less brisant the explosive the more critical the
density factors and cone angles are. Would that be about right?

[DBSP]

Well thats a hell of a difference. Readily made SC are of course very easy to get perfect just stuff it with explosives as you said. The thing is that I doubt that most of us here can get those toys.

The problems with homemade cones isn't the angle of it but rather the seal of the gap created when fou fold the sheeting into the cone shape. It's very easy to solder it but extremely hard to get the solder to be as accurate an minimal as possible so that the cone will act just as it would if it had been pressed from a sheeting in a mould rather than cut out and soldered. The solder is normaly where things get fucked up.

It's not the easiest thing to get the thing completelyy round before it is soldered. Unless of course you've got access to a machine that bends metal sheeting bu passing it between two cylinders/cones thus bending it by decreasing the distance between the cylinders/cones with decreasing of the distance each time you pass it throug the machine.

[Cricket]

I have never made a SC or cone. But it would seem to me someone could melt Cu and pour it into mould of the desired shape. Then press another cone of the same proportons into the first cone. A lip the height of the desired thickness of the cone could be placed around the top of the first cone to give a more precise cone. I don't know how different the properties of cast Cu would be, but probably not so much as to cause a malfunction. Also, it might should be cooled slowly to make it less brittle.

[Mr Cool]

Copper would be too hard to cast without a lot of work. Use lead or tin instead.

[Cricket]

Yea, I was wondering if lead could be used in a SC. I have plenty of it from shot shells. Also, would there be an alloy that is better than a pure metal for a SC?

[nbk2000]

Siince the topic of forming copper into SC cones came up, I thought I'd post this PDF I made from a book on copper forming.

Specifically plates (EFP platters) and how to anneal copper and clean it.

[Mr Cool]

In the past, there has been some discussion on using metal powders in some sort of binder as a liner, and many people doubted that it'd work.
Well, I've just read on a site about clearing mines/UXO that fibreglass (glass fibre/resin composite) liners have been used, so I see no reason why resin/metal could not be. It would be more similar to a sintered, rather than solid, liner, but it should still work fine. One problem that I forsee, however, is making the liner of an equal thickness all round. It'd be hard to mould the metal/resin, since it'd be viscous and the liner will need to be thin, also the mould would need to be put together very accurately.
If using fibreglass, it is easy. You just grease up a cone (turned from wood or whatever), put fibreglass on it, then spread resin/catalyst onto the fibres and scrape off the excess. This will create an even thickness. But this liner would be of a low density, and not as effective. And I doubt that metal/resin would soak into the fibreglass very well.

Any ideas on how one might creat a metal/binder liner? The binder doesn't have to be a catalyst-activated resin, it can be any common substance that you think is suitable.

[nbk2000]

Silicone rubber chaulking loaded up with metal powder, perhaps?

[yt2095]

many years ago I used to use an over the counter (fron a car fixing shop) compound called Chemical Metal (I don`t remember who made it, Evo,Bostick,Araldite?).
it boasts 55% metal content, and when set it`s about as hard also. I think the metal was some Stainless steel (the Cr/Ni ratio I don`t know) it`s non magnetic however.

I used to coat sensitive circuitry in this, for protection and prying eyes.
at 55% I`m unsure if it would be good enough for a liner, but it`s the closest I know to.

[GibboNet]

You could make a liner out of most of those I'm sure, but I think if you used any binder, and the usual metals you're off to a good start. I'm not sure why, it seems obvious to me, (have I missed something ?) but couldn't you make a liner by moulding between two identical cones ?

Actually, with some mathematics, you could work out what you needed to make a single cone out of sheet metal, that was exactly the diameter, height, and width you wanted it, then make another identical. Then, get your mix of metal powder and binder, and pour it into one of these cones, then sit the other inside the first, so that the mix is set between them, which should make it even.

I'm trying to make a picture, but my 3D graphics program hates me, and I can't make exact angles in photoshop. Anyone know what I mean ?

Of course, if you can make the original cones, then you should be able to make liners the same way... Of course this way, the cones can be any metal, and the liners can be made from any metal powder, and any binder, which means depending on setting times, you could pump out a few at a time, with a waiting period only for drying.

The same could be done with circular, to make the bowl shaped platters.