Nitrocellulose granulated black powder.

[AussieBombTech]

I have been doing a lot of work on the best possible granulation method that a lot of beginner pyros can do.

My first method was the original dextrin binding. 5% dextrin to 100g black powder. Made into a damp putty and pushed through a metal screen or mesh.

 

This method makes nice granules but are not that strong, they tend to crumble when a shell is placed on top thus compromising the lift. They are easy to make and dextrin is easy to acquire.

 

My next method was the crushing method. I made a big puck of black powder with 5% dextrin to 100g black powder, I then let that dry and crush it up in a mortar and pestle.

I separated it with the respective sieves and sizes.

 

Works nicely. A little bit more work and you dont get a consistent grain size but they are much stronger and burn nicely.

 

My final and favourite method is the nitrocellulose method. I take 5g 100% nitrocellulose I made using nitric acid and sulphuric acid and nitrated cotton for 30 mins to acetone. I added all of the nitrocellulose lacquer and and mixed well. This mixture dries very fast and was easy to work with, also very forgiving if you added to much NC. Some people use the puck method for this but I found pushing it through a mesh screen worked better, if you need granulated BP fast this is the way to go. It dries within minutes and burns faster than all the others. It also makes very strong granules that tend to stay in one piece when a shell is placed on top.

 

Thank you for reading, I hope you enjoyed. I put a lot of time into this so please be sure to tell me what you think.

 

I didnt record or take photos, sorry but I will next time I make a batch, Im currently working on purple stars.

 

ABT

[NeighborJ]

I find it surprising that your BP made with such high percentages of dextrin were so structurally weak. Most pyros use amounts around 2-4% and have no issues with crumbly grains. I suspect the dextrin you are using is either sub par or home made, using good quality dextrin will make very hard durable grains when made properly.

 

Pucking and corning does not use any binders. It makes such hard grains that no binder is needed. It also is arguably not suitable for everyday pyro purposes. The higher density grains makes a slower burning powder which is suitable for use in firearms and cannons which use the push of the slower burn but it isn't as vigorous as a screen granulated powder which creates a more explosive and instant release of energy required for lift and burst in shells. Often a light dusting of graphite is used to coat the grains to enable them to be handled without breaking up by allowing them to slide past one another.

 

Many people use an alcohol granulation prosess without a binder to ensure the best and quickest release of energy for pyro aplications. This is arguably the best and hottest powder which covers all the bases, including the hard grain aspect.

 

N/C granulated powder when compared to all the other methods creates the slowest powder when compared to the rest, provided they were all made properly and with good quality chems. The N/C burns at a much slower speed than does BP, as a result, it inhibits the reaction a bit. Most people don't make their own N/C, the lacquer is often made from double base powder which doesn't present the same storage degradation issues which 100% N/C does. Most people don't want it to burn their shop down if it has been stored improperly for too long.

Edited September 23, 2018 by NeighborJ

[Merlin]

I still use Dex/ water to bind BP but I can't help wondering if one used alcohol and phenolic resin what the result would be? Very hard grains that maybe augmented by the phenolic?

[Mumbles]

I agree partially with NeighborJ. If NC granulated BP is harder than BP with 5% dextrin, you're doing something wrong. Based on the fact that you can break up the puck that was made with dextrin further supports this. Then again you mention nothing about pressing force, if it was even pressed at all, so who really knows.

[AussieBombTech]

I still use Dex/ water to bind BP but I can't help wondering if one used alcohol and phenolic resin what the result would be? Very hard grains that maybe augmented by the phenolic?

That’s a good idea. I may have to give it a go. I can’t imagine it would be better than dextrin though

[AussieBombTech]

I agree partially with NeighborJ. If NC granulated BP is harder than BP with 5% dextrin, you're doing something wrong. Based on the fact that you can break up the puck that was made with dextrin further supports this. Then again you mention nothing about pressing force, if it was even pressed at all, so who really knows.

 

I’m not actually doing anything wrong. Sometimes heavy shells break granules. It’s the puck method so it has to be pressed. It was pressed with a hammer in a piston. Remember this post is for beginners in mind.

[AussieBombTech]

I find it surprising that your BP made with such high percentages of dextrin were so structurally weak. Most pyros use amounts around 2-4% and have no issues with crumbly grains. I suspect the dextrin you are using is either sub par or home made, using good quality dextrin will make very hard durable grains when made properly.

Pucking and corning does not use any binders. It makes such hard grains that no binder is needed. It also is arguably not suitable for everyday pyro purposes. The higher density grains makes a slower burning powder which is suitable for use in firearms and cannons which use the push of the slower burn but it isn't as vigorous as a screen granulated powder which creates a more explosive and instant release of energy required for lift and burst in shells. Often a light dusting of graphite is used to coat the grains to enable them to be handled without breaking up by allowing them to slide past one another.

Many people use an alcohol granulation prosess without a binder to ensure the best and quickest release of energy for pyro aplications. This is arguably the best and hottest powder which covers all the bases, including the hard grain aspect.

N/C granulated powder when compared to all the other methods creates the slowest powder when compared to the rest, provided they were all made properly and with good quality chems. The N/C burns at a much slower speed than does BP, as a result, it inhibits the reaction a bit. Most people don't make their own N/C, the lacquer is often made from double base powder which doesn't present the same storage degradation issues which 100% N/C does. Most people don't want it to burn their shop down if it has been stored improperly for too long.

I’m not saying that the dextrin doesn’t work well. The nc burns faster for me. I know what I’m doing when it comes to making it and storing it. I’m trained in explosives and how they are stored. The nc doesn’t degrade as fast as many think, especially in acetone, I also cracked my nc to make it more stable

[Merlin]

Ok I seldom know what all the variables are in a given situation but as for the Dex/water binding I offer a few.

1. Are you absolutely certain that ALL the chems are bone dry? I could imagine that if moisture is present the Dex might not be uniformly incorporated. throughout during milling.

2. Are you using good quality dex or is it home made?

3 Are you sufficiently wetting your milled product and kneading it before screen granulation.

4 Are you sufficiently drying your granulated BP?

5 Finally launch a baseball from a 3" mortar using 25 gram charge. You should get a flight time going up and returning to ground of 10 to 12 seconds if everything has been done correctly.

[rellim]

2% ping pong ball lacquer works well for me. Phenolic resin at 2% is noticeably slower and the grains softer.

 

Speaking of pucks, according to "A Temperature Profile of Study of the Combustion of Black Powder and its Constituent Binary Mixtures",

"hand-packed" BP has a higher linear burn rate than compressed (higher density).

[Merlin]

I doubt anyone would use phenolic to bind BP as water is cheaper than alcohol. But if one did you would have to use a minimum of 6%. 2% is not enough. I wonder how the OP is making BP. 100 grams sounds like maybe mortar and pestle. The only way to use dextrin would be to grind the Dex into the BP as it is prepared not try to add later. I'm just guessing because 5% dex should make very hard granules.

[OldMarine]

You could dissolve the dextrin in the water and knead it into the BP but you'd need to get it mixed very well.

[starxplor]

100 grams sounds like maybe mortar and pestle.

 

I have made 100 and 200 gram batches with a screen, no mortar and pestle needed.

[Merlin]

You can't make hot bp without milling or grinding.Screened green mixed and granulated is pulverone. Maybe I missed it and the OP is making pulverone. But in the 1st post he is saying he is using for lift.

[NeighborJ]

I make hot BP without milling, i use it for lift and burst too. Gotta start with fine charcoal thou. Not many people want to try other methods if the mill is working for them, most people remember how crappy their first batch of BP was without a mill so they never want to try it again. It can be and is done. Edited September 27, 2018 by NeighborJ

[Merlin]

I had a hard time getting my milled BP to where it should be. But since you have a method that works that is great. Is it the CIA method?

[NeighborJ]

Sorta, i use extremely fine milled ERC charcoal and sulfer. I dissolve the KNO3 in boiling water then dump it in with the rest. It is still too wet but i add the fines from the previous batch to soak up the excess water while it is still hot. The mix is vigorously stirred until it starts to cool and thicken. It can then be granulated.

I've noticed little to no change in performance between batches and it works great as standard BP. It isn't crazy hot but it does the job and is easy to make large batches.

[Merlin]

Interesting. I have learned something new. Thanks

[starxplor]

I have made perfectly fine BP with screening alone before I had a mill. The primary trick is to make sure all ingredients are as fine as possible but I also found warm (but not hot) water seems to work better than cold. It might just be better hand work in warm water leads to a more even spread of water in the mix.

[Merlin]

How are you getting the chems fine enough to screen? Just curious. A coffee grinder ormodified garbage disposal? I generally mill 2 1/2 lbs per run ball milling. I use around 40 lbs on the 4th

[starxplor]

My situation is different than most. I can mill the chems individually downstate to get them very fine, and then take them all up north to make BP on-site, where we do not generally have power (sometimes someone brings a generator, but not always).

 

I have not been able to get charcoal fine enough to not need milling for BP with just a coffee grinder.

[NeighborJ]

I buy premilled charcoal from the cookbook or usually cook my own and mill it at home. Regardless the only thing which needs milled is the charcoal. I use hard prilled KNO3 and the agricultural sulfer.

The boiling of the water ensures that a minimum amount of water is used in the process and it needs stirred frequently as it cools to prevent the large crystals from growing.

[Edd]

I’m not actually doing anything wrong. Sometimes heavy shells break granules. It’s the puck method so it has to be pressed. It was pressed with a hammer in a piston. Remember this post is for beginners in mind.

 

 

I’m not saying that the dextrin doesn’t work well. The nc burns faster for me. I know what I’m doing when it comes to making it and storing it. I’m trained in explosives and how they are stored. The nc doesn’t degrade as fast as many think, especially in acetone, I also cracked my nc to make it more stable

 

Mumbles is right. If your NC BP is harder than your dex BP, you're definitely doing something wrong. Or just bad at pyro. Also, the fact that you're apparently trained in explosives here in Aus is scary if true.

Edited September 30, 2018 by Edd

[AustralianPyromaniac]

Mumbles is right. If your NC BP is harder than your dex BP, you're definitely doing something wrong. Or just bad at pyro. Also, the fact that you're apparently trained in explosives here in Aus is scary if true.

 

Edd, there’s clearly some discrepancy between the results here are what would be normally expected. I presume it’s because of the way the meal power is being made (Incorrectly integrated). My guess is that similar to the way Red gum bound BP is much faster than dextrin bound BP when the individual components of the meal are not fully integrated, the NC is speeding the BP by the same mechanism. However, I could be wrong and many others have proposed alternative explanations.

 

I would say that the dextrin you’re using is very low quality though ABT, that shouldn’t, however, slow the BP.

 

The point here is that results speak for themselves. If a test has been done and some conclusion has been drawn, just because that doesn't match with theory doesn’t mean that the experiment itself was flawed much less the experimenter. It simply, in this case, means some factor hasn’t been considered. Your comment is both unhelpful and unnecessary, resorting to insults with no clear gain. Or, you’re just bad at common courtesy.

 

And for the record, I can personally attest to the training of ABT in HE to a level much higher than the majority on this site. I think you would do well to consider that HE and pyrotechnics are very different worlds and knowledge in one field is not transferable to another. Otherwise, as you have found out, you run the risk of sounding like an absolute prick.

[AussieBombTech]

Mumbles is right. If your NC BP is harder than your dex BP, you're definitely doing something wrong. Or just bad at pyro. Also, the fact that you're apparently trained in explosives here in Aus is scary if true.

 

Good one mate, sounding like a tool. Maybe I am bad a pyro, maybe I’m not, as Australian pyromaniac said, this was a test for conclusive evidence FOR ME to see what is better. Again, I’m more suited to high explosives and as he said, they are two very different things. I’ve been doing HE for a while now and to say that “that is scary” is a personal insult. I’d like to see you do what I do. Working with toxic chemicals, highly corrosive acids, carcinogens and explosives is something not everyone can do. You can question my credibility all you want and that’s fine, but I will not take advice from someone who holds no higher authority over me like you. Good day

[AussieBombTech]

I buy premilled charcoal from the cookbook or usually cook my own and mill it at home. Regardless the only thing which needs milled is the charcoal. I use hard prilled KNO3 and the agricultural sulfer.

The boiling of the water ensures that a minimum amount of water is used in the process and it needs stirred frequently as it cools to prevent the large crystals from growing.

if you dissolve your KNO3 in the right amount of water and rapidly cool it in the freezer, powdering is as simple as rubbing it between your fingers