H3 or BP-Rice Hulls?

[TheGandalf]

Hey there.

Can you guys tell me which one of the two burst charges I should use? And what is the difference between them?

Which is best?

//TheGandalf

[nater]

Best depends on what kind of shells you are building and the effect you want when they break.

 

H3 is often used on smaller ball shells since it is more powerful than BP, but can cause stars to go blind.

 

Granulated BP is used as the break charge in most cylinder shells and often used with or without a flash or whistle booster in 3"-4" and smaller ball shells.

 

BP coated on some type of bulking agent like rice hulls, cotton seed or cork is typically used on ball shells from 3" and up. You may or may not use a booster as well.

 

There is no right answer, as long as you find the effect pleasing. I mostly build cylinder shells, so I use granulated BP more than anything. For ball shells and some rocket headers I use BP coated rice hulls with a flash bag if I want a stronger break.

 

I would recommend avoiding H3 until you are comfortable working with potassium chlorate. I would say most people use BP with some type of flash booster. You might get more advice dialing in your shells if you use the most common techniques from current builders.

 

What kind of shells are you building and what effects will you be trying first?

Edited January 23, 2016 by nater

[schroedinger]

That greatly depends on the shells you are building. The H3 charge contains chlorate, which means you need extra equipment for processing it.

H3 is charge much stronger then BP or KP. It can be used with color shells up to 3" without the need of a booster. Coat it onto rice hulls in a 4:1 ratio. In a 4" you will get very hard break, without a thixk prime to surive the hard break 0, else they will blow blind. Also you can use the H3 as the only break chrage in sfera/spiderweb shells up to 6"

[Stef727]

 

Hey there.

Can you guys tell me which one of the two burst charges I should use? And what is the difference between them?

Which is best?

//TheGandalf

 

 

I use Bp rice hulls and 5g of flash ( 3" can shell) and it gives me the most simetrical and breaks I ever got, just make sure that the flashbag is in the exact center of the shell.

[Fulmen]

I made my decision long ago, no chlorates period. It's doable, but require more equipment and tidiness than I'd like to invest. But it's not like H3 can cover any shell size, and BP/ricehulls alone only works for large shells. Small shells need a hard break, but as the size increases you need progressively weaker break. For a 2" I've used CIA BP and whistle mix, 4-5" works with coated hulls and granulated whistle. I've never used BP/flash much as I prefer a dark break, but I guess that's a matter of taste. Whistle seems to work fine so I've never seen the point of testing other combos.

[pyrojig]

Hot flash and bp hulls works fine w/o the blinding flash everyone hates. I have grown fawn of this mix. It seems like the best use of flash , other than noise. I have tried every mix in the book to get hard breaks and must admit bphulls dusted with flash is a winner , and easy to dial in to your desired burst strength . Start out with less than you think it will need ,then work up from there in gram increments . I prefer ball milled bp , as CIA and other methods result in sub - par qualities . With a decent reactive charcoal and some milling you can get results par with commercial products.

[braddsn]

Gandalf: I suggest starting with MCRH 7:1 (bp:hulls), and using a slow booster formula to dial in the power of the break. For the following shell sizes, start with the following amounts of slow booster and work from there. 3" use 3g, 4" use 4g, 5" use 6g, and 6" use 10g. The formula for the booster is 35KCLO4, 35KNO3, 30 Dark AL. The slow (spanish) booster is a little more forgiving than 70/30, thus reducing chances of blind stars. Also, make sure there is plenty of prime on your stars and you can break em super hard and still get reliable ignition.

Here is a 3" shell broken in this manner:

 

https://youtu.be/-X7wXMOlLpo?t=8s

Edited February 1, 2016 by braddsn

[Eyegasm]

Regarding rice hulls. Last year I went after a few combines with a bucket and 3/8" square mesh and collected about 4 buckets of wheat husks. I really wanted to try processing them with BP and seeing if they are a viable alternative to rice hulls. This past year was nothing but a time vacuum. Has anyone here ever attempted something like this? If so what were the results?

[schroedinger]

I used, grass seed, barley and husket hulls. All work. But the grass seeds and husket are only good up to 3". Also grass seeds can be interesting in charcoal star shells, if your shell needs to gain some weight. Barley can be used just like rice hulls.

[Seymour]

So long as it is not too compressible, any cheap granular material can be coated with a bursting composition to break shells.

 

I still prefer the method using rough powder (screen granulated, or in my case, grater granulated) to burst shells and if using it like that means too much burst is used for the particular effect, cutting it with dragon flowers, small strobes and other "non inert filler".

 

But I accept that economics is often relevant.

[schroedinger]

Well seymour while using rough powder works, and is a normal part of some shell types like e.g. sfera shells. It has some big disadvantages, 1. It eats up chemicals like nothing 2. It is heavy. I just imagine a 8 " ball filled with about 4 kg rough powder.

[lloyd]

I disagree, Shroe. "Rough powder" as used for burst is screen-granulated, and called "polverone". It is not particularly dense, weighing considerably less than would corned powder of the same volume. It certainly does NOT 'eat up chemicals like nothing'... it's the least-expensive burst/filler one can use in a shell (which happens to be part of why the Italians began using it! <G>).

 

Lloyd

[schroedinger]

Lloyd yes the italians use rough powder in many paces, as well as fast powder is used, but the big difference here is we talk about cylinder shells, where most times no inert carry material is used. That is different to ball shell, where a coated filler is normal.

Just take a 6" Ball. You need ~300g of hot bp bp on a carrier is needed for braking. But you will need about 4 lb of rough powder or 6 lbs of 2 FA.

 

Even if you take commercial meal-d and coat 350g onto puffed rice you end up with about 5 $ worth of bp. Making 2 kg of of rough powder allready costs about 3$ for the nitrate. If you make hot bp yourself it even gets cheaper.

Edited March 5, 2016 by schroedinger

[lloyd]

Making 2 kg of of rough powder allready costs about 3$ for the nitrate.

-------------------

Huh? I pay about $23 USD for 23Kg! 75% of 2Kg is 1.5Kg, or a buck-forty.

 

Besides, polverone may be finely screened and be coated onto hulls, if that's what you wish to do! <G>

 

In a 3" shell, that wouldn't work... but in an 8"... yes, it does.

 

Lloyd

[schroedinger]

Ok, nitrate is a lot cheaper for you, locally i pay 80 $ bucks for a 25 kg bag, with shipping i pay 60 $. Yes EU sucks whith these things. Used to be 21 $ locally for 25 kg until 5 years ago.

[lloyd]

That would explain it!

 

L

[dynomike1]

The cheapest i could find around here is like $1.00 a lb. @ Coop. Then i would have to drive 40 mi. one way.

[lloyd]

So, buy a couple of hundred pounds! You'll use it!

 

Lloyd

[schroedinger]

Lloyd also some thing i just thought about, for every lb of weight you add to your shell, you need to add 1 oz. Of fast bp for lift. Which makes it a math example.

[lloyd]

Yeah...<shrug> <G>

 

Lloyd

[pyrojig]

In years past I experimented with H-3 in various methods of either ricing or coating on a medium . I read that the consistency in coating or mesh size was pretty important to the performance of the end product. I tried many charcoals , but found literature claimed that to not be as important as in the case of BP./ The more porosity or absorbing nature of the charcoal was important. I always wondered if I was getting the standard mix to perform as Shimizu and Hardt claimed . In their words the burning of H-3 in a open pile resembled a detonation v.s. a deflageration .I personally have never seen this in any of the several attempts to perfect the burst charge. It seemed at best to react like slower whistle fuel. kind of a hissing poof. ( never a heavy thump, like flash) . I am curious if these are the same findings of other members who have made this burst .

 

My intent initially was a complementary burst for kclo3 stars. I was working out a handful of organic color stars from the mentioned authors above . I had "decent" breaks from H-3 but found it underpowered , and shells needed more pasting for optimum breaks. ( opposite of SHimizu's claims).

 

I guess this post kid of got me reminiscing on old attempts and chlorate stars and burst . Any feedback or experience is appreciated .

[schroedinger]

Pyrojig, i maks H3 the following way and get tbe results like described. In the open burn like a hot b.p. with a good wush and a powerfull brake jn small shells if coated onto hulls.

 

Ballmill charcoal and dextrine together, then ballmill the KCLO3. Dump both into a bucket and mix good by hand. Now screen 3 times through a 80 mesh screen.

 

Coat it onto hulls in a star roller using non soaked hulls and a 4:1 ratio.

[Eyegasm]

I am curious. How is your H3 mix with chlorate? I have tried it with perchlorate but never wanted to try it with chlorate due to BP having sulfur in it. I have always heard and read about the dangers of chlorate and sulfur. I never really wanted to try my luck. Any tips on making it safely besides reducing acidity in the sulfur? And how is the performance?

[pyrojig]

Eyegasm: The standard H-3 is just charcoal and chlorate with a non acidic binder like( dextrin) . No sulfur in it ( of course the milling above is done separately, and screen mixed only as stated above )

 

Thankfully the present sulfur is not that acidic like the stuff in the past. When used in shells( H-3 ) on can use bp primed stars , but usually the burst is separated by a thin layer of tissue ( even though SHimizu claimes it fairly safe with out separation ).

 

 

SCHROEDINGER: Are your burning results as described "above " Shimizu's, or what I have found? I use a very similar technique as you describe , and the result is good ,but I was always under the impression that the authors above where getting a much hotter product than I was making .

I guess a fellow enthusiast made chlorate based comets , and while shooting the 3" comets out of the guns he was getting detonations . I think he was trying to make glitter and other streamer comets . After ruining several guns at a event, he resided to remotely burning them to destroy the failed comp. He painfully reported ,that the several pounds of comp he fuse lit and retreated a distance from went into a full detonation .

[schroedinger]

Yes it works just like described above, in the open like a nice hot bp, in a shell up to 3" you don't need a booster. In a 4" color stars tend to blow 90% blind.

In a 3" you need to use color stars of max 6 mm (w/o prime) or the pattern is to sparse as the break radius is quite huge.

 

You can use H-3 for lift in cake sized items, but then as a meal powder. I tried once to use it as 3 FA sized in a 3", well one more mortar in heaven.