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Posted (edited)

Here are my first two 3" shells.

Inner diameter: 64 mm.

Star composition:

NaNO3 - 65%

Suplfur - 20%

Pine Charcoal, ballmilled - 15%

+ 5% Dextrin

+ 3% MgAl

Star size - 10 to 10 mm, cylindrical.

7 layers of 12 stars in each layer.

Ignition Tube inner diameter - 6 mm, outside diameter - 9 mm.

 

Burst charge:

Nitrate flash KNO3 50% Suplfur 30% Al 325 mesh flakes - 40 gramms.

Granulated, granuls 1.5-2 mm.

Delay - 2.5 sec.

 

skNagtv6GJI.jpg

 

klDZ3CZrHwY.jpg

 

DGhqCBmaxcU.jpg

 

AIufgsQI6gA.jpg

 

Paper cap to prevent ignition while working with the shell.

s6JQq8fVOa8.jpg

 

The second shell:

Star composition - Tiger Tail,

Star size - 20 мм

Burst - 16 gramms of the same nitrate flash.

2" shell star comp is the same as in the first 3" shell.

 

sbzGZCGuLdE.jpg

 

sbWb4w-U3co.jpg\

 

99Bhi-yQ3d8.jpg

 

tBRnqvFshvY.jpg

 

 

p5syUlC2Dyo.jpg

 

dBWHEMTMaVM.jpg

 

excnqTdtYdo.jpg

 

tz1wiO5mPrQ.jpg

 

When I was shooting the second shell, the rain began, so I had to make everything fast, so I forgot to turn on the right program and thats why the camera lost the focus.

 

VIDEOS:

First shell:

https://www.youtube.com/watch?v=hkDLzzZpiz0

Second shell:
https://www.youtube.com/watch?v=k2d7CtlqahU

 

Can you help me with the burst for the second shell? I think I need a faster burst.

Edited by Maxim
  • Like 4
Posted

Nice pictures of the build. Good work. Did you fill in between your stars and the edge of the canister?

Posted

No, the burst charge is only in the center of the shell, :)

Posted (edited)

Use 5:3:2 KNO3:Al:S for optimal burst charge. And if that doesn't work use finer Aluminum like german dark or indian blackhead.

 

Also damn those are some nice 3" shells if they're your first.

Edited by OblivionFall
Posted (edited)

Nice work. In fact it looks so good that it could be that you have been doing this longer than you admit. :)

 

 

Oh yah, on that second video, I hate it when that shyte happens when the camera starts screwing with the focus. Happens right when you least need it.

Edited by Sparx88
Posted (edited)

Here are my first two 3" shells.02

02Inner diameter: 64 mm.

02Star composition:

02 NaNO3 - 65%

02 Suplfur - 20%

02 Pine Charcoal, ballmilled - 15%

02 + 5% Dextrin

02 + 3% MgAl

02Star size - 10 to 10 mm, cylindrical.

027 layers of 12 stars in each layer.

Ignition Tube inner diameter - 6 mm, outside diameter - 9 mm.

02

Burst charge:

02Nitrate flash KNO3 50% Suplfur 30% Al 325 mesh flakes - 40 gramms.

Granulated, granuls 1.5-2 mm.

Delay - 2.5 sec.

02

skNagtv6GJI.jpg

02

klDZ3CZrHwY.jpg

02

DGhqCBmaxcU.jpg

02

AIufgsQI6gA.jpg

02

Paper cap to prevent ignition while working with the shell.

s6JQq8fVOa8.jpg

02

The second shell:

02Star composition - Tiger Tail,

02Star size - 20 §Þ§Þ

02Burst - 16 gramms of the same nitrate flash.

022" shell star comp is the same as in the first 3" shell.

02

sbzGZCGuLdE.jpg

02

sbWb4w-U3co.jpg\

02

99Bhi-yQ3d8.jpg

02

tBRnqvFshvY.jpg

02

02

p5syUlC2Dyo.jpg

02

dBWHEMTMaVM.jpg

02

excnqTdtYdo.jpg

02

tz1wiO5mPrQ.jpg

02

02When I was shooting the second shell, the rain began, so I had to make everything fast, so I forgot to turn on the right program and thats why the camera lost the focus.

02

02VIDEOS:

First shell:

https://www.youtube.com/watch?v=hkDLzzZpiz0

Second shell:

https://www.youtube.com/watch?v=k2d7CtlqahU

02

02Can you help me with the burst for the second shell? I think I need a faster burst.02

very very nice work..!! Edited by swapnilsutar1988
Posted

Excellent! I couldn't see the blurry one very well, but the first shell was outstanding! I love it. Nice break and nice colors.

Posted
Can you help me with the burst for the second shell? I think I need a faster burst.

 

Just speculating here, but you could play around with the size of the granules. It's either that, or move to a different, faster flash altogether.

I'm thinking smaller, for a faster energy release. The question is how small you can go before the flame-front starts to be slowed down by the lack of clear pathways for the hot gasses.

Then again, salutes work without granules, so it might not be a problem...

 

I'm still blown away with the meticulous builds of your shells. I'd stack the stars, and add all the padding to fit the layer, in one spot, and then just offset where the padding goes on each layer... Your way is better, but i'm not sure the difference is visible. But then, i don't really do cylinder shells, or pumped stars. I just know thats how i would do it, since i'm prone to shortcuts...

Lovely work.

B!

Posted

Please don't take these comments as too critical. The first shell worked great, and I have some general idea about the second one.

 

This said, I don't think you need a faster burst. I think you need a better burst. That or there are some major construction flaws that I'm not seeing. I'd lean toward better burst however. The casing looks fine. You're already using a huge amount of flash, and double the normal amount of spiking. The issue I think you're running into is that flash powder produces very little gas output, and on it's own is sort of a sub-par burst. I believe if you mixed in granular black powder, or even polverone, you'd have much better breaks. Burst is about both speed and gas output. If you lack one of them, your shell wont burst to it's full potential.

 

I also believe you'd also get better breaks if you filled in the spaces between the comets and the wall. Doing this with something flammable and gas producing like polverone might actually be enough to solve your issues.

 

Your star sizes don't quite make sense. To fit 12 comets per ring, they should be around 13mm OD. For the second shell, I bet you can increase the inner diameter a couple millimeters and fit 7 comets quite snugly.

  • Like 1
Posted (edited)

I agree with Mumbles 100%. I get great break action by using a 60/40 mix of BP/Flash and usually dust polverone among the stars. I have found more flash than that can actually take away from the effect of the stars (bright flash.. your eyes take a moment to adjust and you miss out on the stars). My flash is perchlorate and 325 mesh bright flake aluminum. I saw the your video where you lit your BP on your hand; That's some dam hot BP! You should have no problems using that in your break charge

Edited by MadMat
Posted (edited)

Thanks for everything, I have one more question, what's polverone?

Yeah, the stars were actually 13 mm, not 10.

Edited by Maxim
Posted (edited)

Unmilled dry mixed/screened BP.

 

It's nice because it burns much slower than the burst creating a larger longer lasting fireball to help light the stars etc. Don't use it with the burst, only around the back side - between the case and the stars/ inserts. Helps stabilize and firm up the shell too.

Edited by Sparx88
  • Like 1
Posted

When I make polverone, I still ball mill it for 30-40 min.s. IMHO it's easier than screening :P

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