Crayon Boomerite

About a month ago daughter Kim sent me a video of someone successfully making colored smoke bombs using “oil crayon”. I couldn’t find the type of crayons I think they were using in the video but I did find some cheap bulk crayons on Amazon and ordered them:

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We know that if we put several pounds of colored powder on top of an exploding target it will disperse the powder into the air and give some color to the explosion. But it would be nice if the explosive itself also resulted in colored smoke. I also ordered some colored corn starch powder from Amazon which I thought also might be worth a try:

Last Saturday, December 16th, we melted the crayons in an electric skillet.

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Then added the ammonium nitrate.

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Then we mixed in the other ingredients to make Boomerite.

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We also made a batch of Boomerite with a cup of the colored corn starch powder mixed in.

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We then took the targets out for testing. None of the targets resulted in any colored smoke.

I knew the additional ingredients would make detonation harder so I used 50 grain VMAX ammo in a .223 rifle with a 24 inch barrel to get the best velocity and expansion for a better chance of detonation. All the targets hit with these bullets, from 20 yards away, detonated. The velocity at the target was probably just over 3300 fps.

Hitting them with slower FMJ bullets, as fast as 3200 fps, just punched holes in the target. A slower expanding bullet once resulted in a small pop which destroyed the target.

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Although we didn’t get any colored smoke we did manage to blast away quite a bit of the little berm we were shooting into. In the picture below the small mound of dirt the target is sitting on use to extend parallel to the target across where the crater is now.

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13 thoughts on “Crayon Boomerite

  1. Pingback: It’s going to be a white Boomershoot Christmas | The View From North Central Idaho

  2. So the binary explosive is Ammonium Nitrate and powdered Aluminum.
    A Pyrotechnic mixture. Read up on it. To get colors you will have to add the appropriate Nitrate Salt. Barium for green, Sodium for yellow, Strontium for red, etc.
    What percentage I don’t know, experiment to find out.

    • Boomerite is not a binary explosive and it doesn’t use aluminum. The colors from barium, sodium, strontium, etc. appear when the electrons fall from a high energy state to a low energy state, i.e. during the burn phase. They would only change the color of the flash, not the smoke. The flash of an explosive is extremely short. Only rarely do we see it with Boomerite and then only when we add an additional fuel, such as the corn starch powder or crayons see here, which is burned “long” (milliseconds) after the explosion is over.

  3. Joe the “crayon” you’re looking for may be a grease pencil or paint crayon like what welders use to mark up a piece of steel.

  4. I have used a gallon ziplock baggy of charcoal briquettes on top of a pound or so of ammonal (Tannerite, more or less) to emulate a TNT explosion. This looks like the black soot cloud of a negative Oxygen ballance explosive, works well enough so some veterans have hit the deck on witnessing.

    For civil war reenactors, same thing but use a gallon baggy of barn lime instead of charcoal. Huge cloud of white “smoke”, emulating a black powder filled artillery shell.

    You can try the big bottles of colored chalk line chalk powder from Home Depot/Menards, it sort of works, but is really too expensive for the effect produced. Kind of “tints” the cloud of water vapor/Aluminum oxide the color of the chalk, but is nothing like the intense color of a chlorate/lactose/aniline dye smoke device.

  5. Pingback: SayUncle » I’m sure there’s another way

  6. You will probably need an industrial smoke dye. KoR did a video on it here :
    https://www.youtube.com/watch?v=7DVpSFL_bFA

    Not sure if the same stuff will work in your application, but might be worth checking out. He does not have a link to the supplier since they only seem to deal in bulk, but if he was able to wrangle out a few one pound sample packs from them to test with you may be able to as well.

    This appears to be the company they mentioned: http://www.coloredsmoke.com
    good luck.

  7. The synthetic dyes are vaporized by the chlorate:lactose mix, the carbonates serve several functions: Diluents to cool off the reaction and ensure that there is a porous ash the vaporized dye can blow through and escape the device. Carbonates on heating release CO2 and become oxides- Which are quite refractory, and the escaping CO2 keeps atmospheric O2 away from the voltailized (and FLAMMABLE) dyes until they have moved away from the device and cooled a bit. Ever see a consumer smoke device just emit a flame, with little or no color? That’s because the dye BURNED.

    I have no idea if mixing dye directly into your ammonium nitrate explosive will work to vaporize the dye without burning it, this is a narrow line in deflagrating devices.. I would be interested to see how that went. Good luck if you go there-

    I must mention that the Potassium chlorate/lactose combination is nearly as sensitive to friction as chlorate/Sulfur. Be careful, I knew someone who died of burns received while mixing a batch of smoke composition which caught fire.

  8. Colored corn starch powder. Its available on amazon and is what is mostly used for those gender reveal videos. It makes a really nice “cloud”

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