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Crazy comet


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#1 Uarbor

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Posted 26 June 2022 - 07:43 PM

I thought I would go with half mill dust and half Tiger Tail composition with a pinch of crackle. Primed with nitrocellulose lacquer and granulated black powder. They just won't light until apogee. I must say I love the effect I think I might just shorten the length to about half of what it is. It actually looks like a real Comet at first and then the chickens get a wake-up call LOL I figured this one might come back so I waited till right after a downpour.


Edited by Uarbor, 26 June 2022 - 07:43 PM.

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#2 SharkWhisperer

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Posted 26 June 2022 - 09:52 PM

NC lacquer is a barrier to ignition. Maybe counterintuitive because it is flammable but it's a crummy solvent for ignition. Those comets would have fired up right out of the tube with a water/dex spray and BP, though you probably didn't need any prime at all. The TT/mill dust is hot enough to fire up your crackle scraps and your lift will almost certainly spark up those comets without priming. Priming (without NC!) can be good insurance and I've done it before, but it has been many years since I last primed charcoal stars like TT, C6 etc and don't have problems with stars or comets blowing blind. It's just a wasted step for me. That comet turned into a metor! Try it w/o NC. Also, dip a piece of visco in NC laquer and fire it up. The flame will preferentially shoot out the open end while the NC burns sloooowly as it catches up. NC has uses but it is not good for priming anything. Imagine a shell with a hundred stars of that comp, primed with NC and all firing up on the downtrip. Yipes. You'd want to be wearing a Nomex fire suit. There's night-n-day difference between high surface area guncotton that burns almost instantly and a hard shell of dense NC. I used it as a carrier for pyrogen on nichrome motor igniters/ematches like many do, but dumped that in place of rubber comps that burn faster--with faster pyrogens the NC shell was a barrier that was getting ruptured before igniting.



#3 Uarbor

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Posted 26 June 2022 - 11:35 PM

NC lacquer is a barrier to ignition. Maybe counterintuitive because it is flammable but it's a crummy solvent for ignition. Those comets would have fired up right out of the tube with a water/dex spray and BP, though you probably didn't need any prime at all. The TT/mill dust is hot enough to fire up your crackle scraps and your lift will almost certainly spark up those comets without priming. Priming (without NC!) can be good insurance and I've done it before, but it has been many years since I last primed charcoal stars like TT, C6 etc and don't have problems with stars or comets blowing blind. It's just a wasted step for me. That comet turned into a metor! Try it w/o NC. Also, dip a piece of visco in NC laquer and fire it up. The flame will preferentially shoot out the open end while the NC burns sloooowly as it catches up. NC has uses but it is not good for priming anything. Imagine a shell with a hundred stars of that comp, primed with NC and all firing up on the downtrip. Yipes. You'd want to be wearing a Nomex fire suit. There's night-n-day difference between high surface area guncotton that burns almost instantly and a hard shell of dense NC. I used it as a carrier for pyrogen on nichrome motor igniters/ematches like many do, but dumped that in place of rubber comps that burn faster--with faster pyrogens the NC shell was a barrier that was getting ruptured before igniting.

I shot two of them unprimed and they behaved the same way. Except for they did not make it to the ground apparently the NC lacquer slowed it down even more. I even tried roughing up the surface of the second unprimed comet and it was the same I think it's just a bad comp or maybe I pressed them too hard at 5,000 pounds Force which at an inch and a half is 3300 PSI. They were harder than woodpecker lips I could barely scratch it with my pocket knife

Edited by Uarbor, 26 June 2022 - 11:36 PM.


#4 SharkWhisperer

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Posted 26 June 2022 - 11:59 PM

I shot two of them unprimed and they behaved the same way. Except for they did not make it to the ground apparently the NC lacquer slowed it down even more. I even tried roughing up the surface of the second unprimed comet and it was the same I think it's just a bad comp or maybe I pressed them too hard at 5,000 pounds Force which at an inch and a half is 3300 PSI. They were harder than woodpecker lips I could barely scratch it with my pocket knife

Ooh, sounds dense. Well ya might want to prime those with some bp then, hah ha! Might even add a little Si to get 'em hot fast. Nice effect if you can avoid starting a fire!



#5 kingkama

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Posted 27 June 2022 - 11:30 AM

Spray them evenly with water, then mix them together untill they start to be slymy on surface, then drop them in a slow bp dust. They have to be bone hard so the moisture didn't penetrate fast. I se somewhere peoples put in water in a sift then pull it out shaking for remove excess water then slow bp dust with some destrine inside. After drying they catch fire from the first moment doingthe trik. Try and let me know.

#6 Uarbor

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Posted 27 June 2022 - 08:10 PM

Spray them evenly with water, then mix them together untill they start to be slymy on surface, then drop them in a slow bp dust. They have to be bone hard so the moisture didn't penetrate fast. I se somewhere peoples put in water in a sift then pull it out shaking for remove excess water then slow bp dust with some destrine inside. After drying they catch fire from the first moment doingthe trik. Try and let me know.

will do

#7 Arthur

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Posted 28 June 2022 - 09:40 AM

At the Royal Gunpowder Mills (local to me) they have designs for large pellet BP powder which were  14mm hexagon with a number of holes through. The outside burned regressively  but the inner holes burned progressively. Having a hole through your comet would make it burn out faster. Sending it higher would mean it had further to fall.



#8 kingkama

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Posted 29 June 2022 - 12:30 AM

At the Royal Gunpowder Mills (local to me) they have designs for large pellet BP powder which were  14mm hexagon with a number of holes through. The outside burned regressively  but the inner holes burned progressively. Having a hole through your comet would make it burn out faster. Sending it higher would mean it had further to fall.

They Will break apart and Need ti be closed in a paper bags before shooting.




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