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Cyclonite
May 5th, 2003, 08:20 PM
You can achive near simultaneous detonation without det cord by useing basting caps or something improvised to that extent to detonate multiple charges by having the caps open end pointing to the direction of the explosive initiated with fuze. This does work with C4 and military basting caps, it has alot of applications if one is trying to obtain a specific explosive effect on the object of choice without det cord. Has anyone tried this with AP or something similar? For the main charge I suspect a HE with a semi-high VOD would have to be used to initiate the other charges. I searched on this subject and didnt come up with anything and thought it was worth discussion.

Axt
May 6th, 2003, 02:54 AM
Curiousity got to me and i tried it, though didnt work.

<a href="http://www.fnphost.com/sites/good/nice/annmsp.jpg">Attempt</a> (download and rename .jpg to .wmv)
Or <a href="http://www.geocities.com/roguemovies/index.html">download as mpeg here.</a>


ANNM/SP is no C4 substitute but it was a commercial 8 strength det. in the second charge that didnt fire. Perhaps it was too close? If you can see the movie, the plank shows where it was cut off by the first charge but strangely there was a dent and a bit blown off where the second charge was, ive no explaination for this. The second charge must have partially detonated but you would think surely the det would go before the ANNM/SP, and then you would think that would happen before it was blown away, very strange.

At what distances apart were you using the C4?

Anthony
May 6th, 2003, 03:37 PM
Wrong section first of all...

Sympathetic detonation is a very well documented blasting technique and certainly not a "new" idea that the members here haven't heard of.

Unless you can point to a credible published article/document that supports what you have written, I would think that you have missunderstood the practice.

Only the first charge is fuzed - on of the key advantages of this technique is that you don't need primed charges, which is a lot safer and cuts down on labour/time.

Secondly, there needs to be a medium between the charges that the shockwave can travel through - air is not suitable. Except for charges placed extremely closely, which negates the point of the technique. Water is ideal, wet and/or dense soil is good. Dry/sandy soil is bad, and charges (example: fulls sticks of ditching dynamite) need to be placed as close as 2-3 inches apart.

EDIT: Obviously AP will be good for this, due to it's high sensitivity.

Cyclonite
May 6th, 2003, 06:42 PM
I wasnt saying that it sympathetic detonation a new technique, but anyways I have achived this effect with about a fuzed 5lb C4 charge and the other charges were within 4ft each with a cap like I was explaining with air as a medium. It worked good with C4. I wonder if it would work with a main charge of NG with AP primed charges.

Anthony, yea sorry about the wrong section. But in what I am talking about the charges need to be primed. The main point was that no det cord is needed and the caps (AP) are used to recieve the shockwave which will detonate them Increasing the distance sympathetic detonation can be used. I think AP would increase the distance. I was doing a BIP on submunitions and placed the charges as I explained, the distance of the submunitions determined the distance of the charges (about 4 ft) cause I sure as hell wasnt going to move them and I achieved a highorder on all munitions.

This technique is not documented, its something my co-workers and I talked about and tried.

Anthony
May 6th, 2003, 07:25 PM
My apologies. Unfortunately we've gotten used to newbies coming here and rehashing long known information in new threads they've created - usually having never tried what they speak of, or even really understanding it.

Obviously this isn't true in your case and I thank you for providing some specific info. Practial experiences are welcome and expecially new subjects such as this.

I do have one question for you: is it very important that the open end of the cap in the "slave" charges facing the oncoming shockwave? I.e, if they are just buried randomly in the charges, do the slaves become significantly less sensitive?

Actually, I have another :) What's the relative cost of 4ft of det cord when you're using 5lb lumps of commercial C4? ;)

Cyclonite
May 6th, 2003, 08:08 PM
I always had the caps open end out pointing to the main charge so the Cap is exposed to as much power from the shockwave as possible. In the situation I did this in I didnt bother with hooking up det cord since that would make it more likely to unintentionally move the submunitions that are really easy to piss off:D It simplified things. Explosives that I use in work are payed for by the defense buget (Military) So I use as much as i can and never see a bill:D A little off subject but Iv been reading the forum for a little while and noticed people tend to put thier caps or whatnot near the middle of the charge, I have found placing it near the outside of the charge with the "business end" poked into the charge lessens the chance of partially detonated HE splatted everywhere and may save some of the charge.


Err Sorry I didnt know how the post above was posted, I couldnt delete it

Tuatara
May 8th, 2003, 08:03 PM
That comment about positioning the caps makes a lot of sense when you consider the propagation of the shockwave through the body of the HE. Sorry Anthony, this is a purely theoretical observation :D