Sometimes making things go boom is hard to do!

So I went out to help Joe with some testing today.  Last weekend there were some problems with boomers and testing needed be done to figure out the exact cause of the failures.

Joe and I stopped by the Taj and picked up some equipment however Joe forgot the keys to the magazine and we had to leave the targets that were stored to test how they react over time.

Once over at Mecca we began to mix explosives.  I noticed but didn’t think anything of it that the dust from the bin of KClO3 was less than usual.  Our first experiment was 4 control targets using our standard production methods and baggies with 8 other targets using different packaging methods.  We laid out the first 6 targets.  Two of each.  Loaded up with 62 grain JHP and started on the right. 

Bang, dead center, nothing.  Move to the next one. 

Bang slightly off, bang it’s low, bang it’s high, bang dead center, nothing. 

Bang dead center, nothing. 

Bang dead center, nothing.  Now at this point we’re moving on to the normal production control targets.

Bang dead center…. Nothing. I’m thinking, “what the hell is going on!”

Bang dead center, again nothing.

At this point Joe and I inspect the targets, they didn’t even begin to detonate.  We talk and think well maybe the ethylene glycol absorbed moisture, the bottle is almost empty.  We also realize it’s pretty cold and maybe that’s a problem.

We head back inside to mix up a new batch with fresh ethylene glycol and warm up the targets in front of the heater.  We continue discussing the problems while mixing up the new batch.  I realize that cold can’t be the problem.  A year ago we were detonating with it about 15F out.  At this point we both agree it must be the glycol.

We finish up the targets and take them out to test.

Bang, nothing.

Bang, nothing.

Bang, nothing.

Bang, nothing.  Bag is sitting there because it wasn’t a full square hit.  Throw the bag into the air by shooting the crap out of it.

Glycol is out.  Whiskey Tango Foxtrot!  What has changed!?  We mixed them at Mecca, but how could that cause the recipe to fail?  We go inside again and continue discussing the problem and I start staring at the potassium chlorate.  Finally I ask Joe, “where’s all the dust?”  Normally there’s dust everywhere, this time there’s no dust! 

We start feeling the potassium chlorate focusing our attention on it.  Did it absorb moisture, it’s certainly possible and the texture certainly isn’t right either.  How can we heat it up to dehydrate it?  Finally we decide to head over to his parents place to make use of the stove.  An hour later, the KClO3 is certainly dryer, but the texture isn’t right and there certainly isn’t enough dust still.

We decide to split the amount and make two batches.  Both with the straight freshly dehydrated KClO3, one that has been further ground in mortar and pestle.  A second that has been unmodified and left at it’s current size.  We finish mixing up the batches and have two of each target with a 5th super boomer from the excess left over from each.

We take the boomerite out back and lay them out for testing saving the mix box for later.

Bang, box shredded nothing.

Bang, nothing.

Bang, nothing.

Bang, nothing.

At this point I’m becoming a bit annoyed and disappointed.  I have no clue what’s left.  Joe mentions we could try a V-max bullet.  I’m up for that but my concern is, the past three years I’ve used these 62 grain bullets without a problem.  Joe goes and grabs his V-max mag and I set up the targets left over from the first batch and set up my super boomer.

I tap the mag and charge.  Swing on the first boomer and bang.

Nothing. (expletives run through my mind.)

Bang.   Nothing!

Bang.  Nothing!

Bang. Nothing!

What in the hell is going on.  The last boomer fell over.  I flip on the safety, walk the 25 yards and put it back up right.  Walking back at about 10 yards I say F-it, I’m far enough, it’s not going to blow anyway.  I’ll go entertainingly close.

Bang…….. BOOM!

Immediately I feel my face stinging.  I have a wall of smoke rolling towards me.  I walk back and smile at Joe and say, “Well it worked that time!”  At this point I start rubbing the corner of my lip.  I took a bunch of prills to the face and arm.  Joe even 25 years away said he was feeling the prills.  I clear my weapon and notice something.  This folks is why you wear eye protection!

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You can somewhat see it on the other side of the lens too.  Some of the mud bounced off of me and landed on the other side of the lens.  I had mud on my glasses too.  At this point Joe and I both agree that it’s probably the KClO3, but we don’t know how to quantify it.

We clean up and decide to head back to Joe’s place to do some analysis.  We examine the KClO3 under a microscope.  I think we found our problem.

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I’ll give you a hint, the three items above are KClO3, normal sugar, and flour.  Guess which is the KClO3.

If you guessed in the middle you’re right.  Normally the KClO3 is like powdered sugar or flour.  Doing some research we discovered the Mil-Standard and it appears they have different sizes.

Now we need to try and establish, empirically, which size we need for Boomerite.  Joe’s ordering a flour mill to try and grind the KClO3 smaller, we’re all ears if anyone has any other ideas on grinding it smaller.  Joe has video of the testing and hopefully he posts it here soon.  I want to see that explosion from his point of view.

Barron is the owner, editor, and principal author at The Minuteman, a competitive shooter, and staff member for Boomershoot. Even in his free time he’s merging his love and knowledge of computers and technology with his love of firearms.

He has a BS in electrical engineering from Washington State University. Immediately after college he went into work on embedded software and hardware for use in critical infrastructure. This included cryptographic communications equipment as well as command and control devices that were using that communications equipment. Since then he’s worked on just about everything ranging from toys, phones, other critical infrastructure, and even desktop applications. Doing everything from hardware system design, to software architecture, to actually writing software that makes your athletic band do its thing.

About Barron Barnett

Barron is the owner, editor, and principal author at The Minuteman, a competitive shooter, and staff member for Boomershoot. Even in his free time he’s merging his love and knowledge of computers and technology with his love of firearms. He has a BS in electrical engineering from Washington State University. Immediately after college he went into work on embedded software and hardware for use in critical infrastructure. This included cryptographic communications equipment as well as command and control devices that were using that communications equipment. Since then he’s worked on just about everything ranging from toys, phones, other critical infrastructure, and even desktop applications. Doing everything from hardware system design, to software architecture, to actually writing software that makes your athletic band do its thing.
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2 Responses to Sometimes making things go boom is hard to do!

  1. Wildman7316 says:

    You might want to check what ELSE is in your new batch of Potassium Chlorate, there may have been an “Anti-Caking” Additive included.  Don’t know what all the ingredients are in Boomerite, but since there is a liquid (Ethylene Glycol) in the mix, not sure that the “Grain Size” is going to be that important.

    • There shouldn’t be anything mixed into the KClO3.  It’s mil-spec so contamination from the factory shouldn’t be a problem.  The KClO3 both this batch and the previous do cake like mad and we have to break it apart.  It ends up there’s different grades for particle powder.  Normal anti caking is done by adding desiccant packets as it’s caused by moisture.  The material is double bagged with the desiccant being placed in the middle bag.

      The problem is even after breaking it apart it’s fundamental crystalline structure is larger than previously used.  While a liquid is included, there is no where near enough to dissolve it.  In the mixture it acts more of a binder allowing the KClO3 to adhere to the NH4NO3.  This creates a Oxygen and fuel mixture on the outside of the prill.

      Grain size will affect two things in that, one if it’s smaller it is more likely to dissolve and be suspended in the glycol on the outside of the prill.  Two if it does not, it’s more likely to adhere to the NH4NO3 and be stuck to the prill.  Lastly it increases the surface area allowing the reaction to accelerate more quickly.  Instead of having a wide open throttle, it’s been choked by a more narrow throttle requiring more energy to get going.