Largest

[bigbang]

I tried to search but did not find this question asked. If it has been, sorry, I will keep looking.

What is the largest charge of anything you have "thought" about setting off?

Mine would be last 4th of July, a 4in shell containing 1.5 lbs of standard 70/30 flash made from german dark H and KClO4. It went off about 150 feet in the air. Now all my neighbors call be bigbang, hence the name. This also is what brings me to this site. That much flash gets expensive to make, I am hoping to find a HE that will produce the same results much cheaper.

So far the largest HE (and only one made) was 4gm’s of compressed AP in a
1/2 in. diameter tube 3in. long with an inverted cone made of aluminum foil pressed into the bottom. Nice hole through 1/8 steel. Powerful but not very loud. :rolleyes:

[EP]

Well there are several reasons the pros use flash. Safety is the biggest, you don't really want to be dealing with primaries to launch a shell. Also, HE's sound different, they will be sharper because you'll need a higher VoD explosive for it to work with the minimal confinement that is possible, so no keep ANFO booms. Another big reason is light output, flash will make, as the name implies, a flash! HE's have much lower light output.

If all you've made is AP (hopefully you know this is FAR too sensitive to go in a shell!), you shouldn't be trying to make large HE charges like this.

[bigbang]

If all you've made is AP (hopefully you know this is FAR too sensitive to go in a shell!), you shouldn't be trying to make large HE charges like this.

Yes, I know this, I would never use any primary for a shell. To launch a ~2lb shell you need to use a hell of a lift charge. I wouldn't want to trust any kind of primary in a large amount to that much shock. Primaries are just what they are, Primaries.

I am not to concerned about the flash, I just want the noise. Someday I will start a thread about just that. I started this thread just to see what most people here have done in quanity. :p

[blindreeper]

Well you won't be using any HE in a shell if you know you can't use primarys' in shells, think about it...

[ST]

Theres no reason primaries are any more dangerous then large quantities of flash powder, actually I think it would be safer! After all, HE artillery/mortars etc. do it all the time.

But its fact that flash powder is simply the best for sound and light. Keeping the quantity within reason, are there any HE's that give a bright white flash? Ive never seen any, even when heavy with Al.

[Efraim_barkbit]

400+g ANNM buried in a "sand wall" in a gravel pit (word?)
The most impressive however, was 350g under a couple of dm dry sand and some half m long 2x2 inch wooden boards. it produced an awesome cloud of dirt, and threw pieces of wood high as hell in the air, it´s hard to tell when your seeing the most awesome sight you have ever seen in your whole life,... , but I guess it was well over 30m up, and 50 m away from "ground zero". and that was only ~350g,.
I can´t wait until I can get my drivers licence, after that, THERES NO END TO THE POSSIBILITY

[krimmie]

Yes, I know this, I would never use any primary for a shell. To launch a ~2lb shell you need to use a hell of a lift charge. I wouldn't want to trust any kind of primary in a large amount to that much shock. Primaries are just what they are, Primaries.

I am not to concerned about the flash, I just want the noise. Someday I will start a thread about just that. I started this thread just to see what most people here have done in quanity. :p


If you are not concerned about the flash, how about acetylene and oxygen in a balloon? Makes one hell of a racket without all the safety concerns. The amount of primary it would take to top the noise of 1.5 lbs. of flash is not worth the risk of an accidental detonation. If noise is what you want, stay away from primaries and high explosives...they are better suited for performing work i.e. shattering rock, trees, stumps, small animals in their holes, etc. Whatever you do, be safe so your neighbors don't start calling you "bigbanged" after you get locked up.

[vulture]

If you are not concerned about the flash, how about acetylene and oxygen in a balloon? Makes one hell of a racket without all the safety concerns.

The odds of C2H2/O2 in a balloon going off by static discharge are far higher than well made flash accidently igniting.

[krimmie]

The odds of C2H2/O2 in a balloon going off by static discharge are far higher than well made flash accidently igniting.

Static will set off flash as well. When you say "well made flash", are you referring to the accuracy of the measurements? If so, a poorly made flash would probably take more to set off than a well made one.

If I were to choose being involved in an accident with either, I would opt for the balloon with C2H2/O2!

[bigbang]

With Flash I have found that as long as you are using KClO4 not KClO3 and just Al powder. (No Sulfur) that it is quite hard to ignite with static. I have used a 250,000 volt tazer with the arc going right through a SMALL pile of flash and it will not ignite.

blindreeper: What I meant was that I would not make a shell out of just a primary. Way too much primary in one place for my taste.

Basiclly I was just looking to see if I could make shells much cheaper with a HE. 1.5 lbs of Flash gets expensive. But it looks like everyones attitude is that Flash is the best for noise. I guess it is not that expensive. ;)

[Skean Dhu]

thats why some people choose to use rice hulls /corn cob rather than 1. lbs of anything. If you coat the fluffy media you could probably use around half as much as it would normally take, not to mention be a bit safer in respects with accidental ignition and such.

[Sparky]

What chems are you using? If you are buying german dark aluminum for $27 per pound then I'm not really surprised you are irritated by the expense. Just remember that there are much cheaper versions of flash powder that you can make. Taken to the (sort of) extreme for example you could use potassium chlorate (~$1.5/lb in 1 lb containers) bright flake aluminum (ah, not very much say $7 per lb) and sulfur (dirt cheap - say about $.50 per lb).

At one time I also thought HE's might have a use in making noise for fireworks but now I don't think they would be that great any more. Like people have said the lower boom sound from flash and especially a good BP salute is a better sound (BP is a lower boom than flash of course).

Just on the subject of making loud noises, I remember a noise maker that the special effects guy at the PGI last year had. It was basically a big steel box with some baffles. He had it all set up so he just pressed a button and oxygen and propane would inject. It made one of the loudest sounds I've ever heard (BTW I was about 30 meters away from the 20 lb flash ground salute set off at that convention). Standing 7 meters in front of the box was fairly uncomfortable because of the big shock felt (everyone was holding their ears of course). That's pretty close to be standing, but still I was impressed. Especially because he can press that button pretty much as fast as he wants.

About the oxyacetylene bangs, I've said it before (just ask Bert) and I'll say it again that they were used in display at the last PGI convention in the form of garbage bags full. One of them did go off accidentally during the show so be warned. Probably the cause was a falling spark or possibly static. Their light output isn't much but they do sound nice and loud (not really spectacular). So in other words their performance is ok. But I have heard stories of accidental explosions happening when filling them. Here is one of them (t's in there somewhere):
Oxyacetylene story (google archive of rec.pyrotechnics) (http://www.google.ca/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&threadm=6aQg8.5618%24KA.1215233129%40newssvr10.new s.prodigy.com&rnum=5&prev=/groups%3Fq%3Doxyacetylene%2Bhouse%2Bgroup:rec.pyro technics%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26safe%3Doff%26selm%3D6aQg8.5618%2524KA.12152331 29%2540newssvr10.news.prodigy.com%26rnum%3D5)

[bigbang]

Sparky: Yes I am using German Dark H, I have never tried using bright flake, from everything I've read I didn't think it would work that well. Or is that why you are adding sulfur and using chlorate vs perchlorate?

Skean Dhu: When you coat the media do you just count on the fact that flash sticks to everything it touches? (My wife really appreciates this :rolleyes: ) Or do you use a glue like Dextrin? Perhaps just water?

[krimmie]

Have you considered "cutting" your flash with a triple based smokeless powder? Alliant Bullseye runs about $13.00/lb. My mixture consists of 60%flash and 40% smokeless...sure stretches your flash a bit.

[bigbang]

krimmie: I did try cutting my flash 50/50 and 60/40 with Bullseye last night. I was not impressed with sub 3 gram charges. Does it work better with more confinment or larger quanites? I have been using 1/16 in. wall cardboard tubes for small stuff. (3/8 in. wall for my 4in diam. stuff)

[vulture]

Does it work better with more confinment or larger quanites?

Sjeez! What do you expect! Ofcourse! :rolleyes:

How are you making your flash? Not with "spoonfulls" I hope....

S + chlorate = bad idea like mentioned a 352464245 times before... :rolleyes:

[Arkangel]

Aaaw, don't be mean Vulture, I think he meant "Does it work better with more confinment OR larger quanites" which has a more complex version of "Yes" as the answer.

More containment is the way to make just about any shit mix make a good old boom. If you're getting residue of unburnt compound then you definitely need more containment - set a test charge off in a puddle, as it's the easiest way to spot the residue - the Al makes a sheen on the surface of the water.

[vulture]

I asked because I make deafening bangs out of shitty paint grade Al flashpowder. 1g in a good tube will damage your ears and eyesight if it's made properly.

Hell, if you can't throw together a decent casing...

[bigbang]

vulture:
What I was referring to was 60/40 and 50/50 flash/bullseye mix. a 3 gram charge of straight flash in a 1/16 wall cardboard tube was much louder than either of the mixes, so I was asking basically if the flash/bullseye needed more confinement or possibly a larger charge than straight flash to see the advantage. As for better confinement there is an upper limit when working with over head charges. I would use 1/8 in. 316 stainless if I thought it wouldn’t come back down and kill someone.

btw there are no "spoons" used in my lab, except to maybe move something to my Ohaus tribeam. (for $30 bucks I don't know why everyone doesn't own one.)

Arkangel:
Thanks for the water idea, I will test this and see if any Al is left over.

[krimmie]

[QUOTE=bigbang]vulture:
What I was referring to was 60/40 and 50/50 flash/bullseye mix. a 3 gram charge of straight flash in a 1/16 wall cardboard tube was much louder than either of the mixes, so I was asking basically if the flash/bullseye needed more confinement or possibly a larger charge than straight flash to see the advantage.

I've never mixed Bullseye with only a 3 gram charge. I found that 4 grams flash and 2 grams Bullseye equalled a straight 6 gram charge of flash( in noise). As far as confinment, only cardboard tubes with cardboard endplugs glued on are used around here.

[bigbang]

vulture: I tried some 10g charges and you are right, I can't here the difference. Maybe there is a critical size of a charge using mixed powder. (6g or more)

This afternoon I made a large snow ball with the kids, 3.5 feet around or so. Then proceeded to dismantle it quickly :D . I used a 6g charge of 50/50 mix and put it in the center of the ball. The noise wasn't the usual boom but rather just a heart warming rumble that you felt more than heard. Then the snow ball was no more.