Storing KClO4/Al firecrackers for a long time, possible?

[Pyrostar]

Hi

I made a bunch of salutes using the KClO4/Al flashpowder.
charge is around 1-3g per salute, most of them are polumnas, thumping thunder´s and nitraat crackers,
and because I don´t want to fire them all at one day, I want to store them till new years eve ( 31th decembre).

Is that possible or will the flashpowder become useless over time?
I am using german dark Al, dont know the particle size, but it is darkgrey and clump together.
Potassiumperchlorate is airfloat.

I think around 20g Al-powder is left, is a BaNO3-flashpowder with this aluminiumpowder good?
I have heard it is used as a substitute for perchlorate in pyrotechnic-industries.

Thanks,

Pyrostar

[miech]

Although not recommended, you can certainly store flaspowder containing devices for an extended period of time. As long there is no chlorate/sulfer mix or KMnO4 in it, the risk of accidentially ignition is very small. I would recommend to store them on a cool, dry place, out of the sun and away from possible sources of ignition. Loose flaspowders are dangerous to store, since they only need very little to cause an accident and/or fire.

Nitrate based flashes are safe when the reductor (aluminium) is coated with linseed (or something similar), if they contain 2% boric acid and are kept absolutely dry. Moisture from air can trigger an exothermic reaction between the nitrate and aluminium, since the nitrate ion tends to react like a base under certain conditions.