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Recently I have been using flash powder in a cannon that I made, for a chemistry project, however, it is not causing the rubber ball I put in it to propel out of the tube. First I put in 30g of flash powder, then pack a small wad of paper on top, and lastly insert the ball in an aluminum foil bowl. The fuse is then inserted into the bottom and lit on fire, but the only thing that has been happening is fire flaming from the end of the tube and melting parts of the rubber ball. Do you have any small suggestions, as I am running out of time to figure this out? I attached a picture of the cannon. (Also I do not have time to make black powder). Cannon we have used and others have used before sucessfully

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    $\begingroup$ Just curious about the "running out of time" aspect for figuring out how to get your cannon operable...Aside from that, flash powder doesn't have the bang-for-the-buck that black powder does. You might try compressing and shaping the charge, thereby increasing the energy density and subsequent yield on ignition. $\endgroup$ – Todd Minehardt May 21 at 23:28
  • $\begingroup$ I only have a few class periods left to complete this project and get raw data, so it would be difficult for me to make black powder since it can take a while. How would you suggest I do that? $\endgroup$ – Kenna May 21 at 23:33
  • $\begingroup$ What is your "flash powder" made of? $\endgroup$ – DrMoishe Pippik May 22 at 0:34
  • $\begingroup$ Maybe rather than finishing the cannon project by building a working cannon, instead get some raw data showing why it is not working so well. You could try to measure the volume change from the flash powder, or test whether pumping air into the tube would propel the ball (I don't know how good the fit has to be). Anyway, most projects involve troubleshooting, and most troubleshooting involves testing individual aspects of the problem, and running some positive and negative controls. $\endgroup$ – Karsten Theis May 22 at 17:48
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Flash powder and gun powder are two different mixtures, designed to do two different things. Gun powder is designed to produce a lot of gas very quickly (Carbon dioxide, Sulfur dioxide, Nitrogen) which propels the projectile out of the barrel.

Flash powder - typically potassium chlorate/perchlorate and aluminium powder, examples here and here, produce a lot of heat and light very quickly but not much gas - so no propulsion.

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