Impact exploding stars

[Respirator]

I've had some of Yankie's Flashing stars sitting around for 3+ months in a dessicator, but I only used them yesterday.

 

Fired 2 last night (0.75 inch with 2 sides lightly primed with BP) from a star gun and they each did 4 flashes after their apogee at ~12m, went down and... exploded?

 

The amount of flashing can probably be perfected (that batch was made in a hurry) but I was more interested about their landing. Sounded like a very decent firecracker (or 10) going off. Is this common, for stars to explode violently upon hitting the ground? The surface was concrete.

 

I rarely have stars come down from mines or guns so I was surprised by the concept. Might be something to do with the Al (-400 mesh) since the formula is not too distant from nitrate flash.

[Zumber]

strange..!

I dont believe any explosion by yankies flashing stars just by hitting on ground.

[a_bab]

Could be more of an air reaction. The star is in molten state when it hits the earth (just like all the glitters are) . This will create a splash with a hot, large surface ready to react with air. I do believe it and it's easy to replicate: light a star, wait 3 to 5 seconds then drop it.

 

Your reaction is similar to the ferro-cerium melt splashing, only more violent. (search on youtube).

[MrB]

I to, without any science to back it up, would think it's an instant combustion of the aerosolized molten star as it hits the ground. Similar to high metal content fires and water...

But it's at best a guess.

B!

[pyroman2498]

I don't think it's the star it's self exploding , I think it when it hit it scattered molten AL everywhere and when it did that it reacted with the moisture in the air or on the ground. Al is a very reactive metal when it doesn't have its oxide on it. But still I don't think k it would make a bang like a firecracker but it's possible

[BurritoBandito]

5:3:2 nitrate flash can be initiated by a hard enough impact. I don't know if that's what happened or not, but I don't think it's too much of a stretch.

[pyrokid]

I've noticed a certain phenomenon with Yankie flashers and similar glitter stars. When a sufficient volume of composition is ignited in a static position, a large melt of reactants is created. After a few second delay, all the reactants are consumed in one large flash.

 

Given the large size of the stars in question, I suspect that the melt of reactants hit the ground, and exploded from self confinement.

[psyco_1322]

I've noticed a certain phenomenon with Yankie flashers and similar glitter stars. When a sufficient volume of composition is ignited in a static position, a large melt of reactants is created. After a few second delay, all the reactants are consumed in one large flash.

 

Given the large size of the stars in question, I suspect that the melt of reactants hit the ground, and exploded from self confinement.

 

I've seen this happen myself, testing some win20 stars on the ground. Oddly it would only happen when I burned them in a bucket of ash from the wood stove, on concrete it would not flash off. I figure the hydroxide? from the ash was sort of oxidizing the slag, very interesting effect just to play with.

 

Yankies stars really need to be much smaller, saying 1/4" - 3/8", this still gives several flashes but lets the stars get consumed. They are a really neat effect but I think they pose more of a fire hazard than anything.

[Sparx88]

Same here, even at 3/8 with prime at an average 200 ft lift in a 3" with medium break they burn long down past the tree tops. I tried these out mainly because I lack all the goodies to make "real" glitter or strobes. They look pretty cool, would like to see what they look like when done right and in a larger shell.

 

I will say that they do pop and snap a lot when lit static on a steel plate for testing so having one bang does'nt sound far fetched.

Edited July 27, 2014 by Sparx88