KCLO4 Black Match

[chemtech89]

So I’ve decided to experiment with different black match recipes. First off I used KCLO4 black powder 75:15:10 with 5% Dextrin and 4 hours in the ball mill. Rolled cream n sugar cotton string in a hank and needed it with composition and 75:25 water: alcohol. The string has a very good coating and it fully penetrated the string, no white core at all. The string is still fully drying but I did a small test with about 6" long piece, after sitting in front of a low heat ceramic heater until it was stiff. Now, I don’t know if the quickened drying method caused this or if this is will be the nature of the BM(when rest is fully dry) but when it ignites, it burns with a bright powerful yellow flame and burn the string fully. HOWEVER! it doesn't keep going out when lit. When it does burn it burns great, but quickly goes out and doesn’t easily stay embered to re-light itself. It was a very nice burn, fully consumed the string.. The things I don’t like about my current black match (BTW this was my first time needing a hank of string, prior i used a BM machine... pulling string trough funnel filled with slurry) is that it just burns the coating on the outside, so after the QM brakes apart i have burned strings scattered at my launch site.

 

So, I am pleased with this (still not fully tested) BM from the strings complete burn... It looks more like visco when it burns, very nice. But it does want to keep going out and once again this was for the small quickly dried test piece, not the full amount this is still slow drying. So I will update when that’s finished drying.

 

I have tried to research to find anyone else that has tried this usually burst comp on BM but have not found any results. So, my apologies if this has been covered.

 

My thoughts are that if the full batch does burn the same way, I’m sure it will work in a leader pipe but I want something that will burn fully on its own without the aid of 3 other burning strings. So, if this is the case I may add more of the oxidizer on the thought that it will compensate for the string being burned.

 

Any thoughts or suggestions about the BM or more specifically adding more KCLO4?

Edited October 18, 2012 by chemtech89

[fredhappy]

chemtech: it is nice to experiment, but please be safe.

 

It is generally a bad idea to mill mixtures containing KCLO4 and sulphur. These mixes are surprisingly sensitive to shock and friction. What you have been doing basically is milling KP which really is a big pyrotechnic nono.

 

The reason KCLO4 is not used in blackmatch is due to these sensitivity issues. I would feel very uneasy in using scissors or a knife to cut a piece of quickmatch containing this KP based blackmatch.

 

There has been an accident where someone was fatally hurt when a shell went off whilst he was using a stapler to attach the leader match to a mortar rack. One of the parts of investigating that accident focused on the blackmatch being contaminated with KCLO4 and therefore potentially being set off whilst mechanically manipulated ( the stapler).

Edited October 17, 2012 by fredhappy

[chemtech89]

No wonder I couldn’t find anything on this. I am extremely great full you told me about this, thank you very much! I was under the impression that just chlorates are unsafe with sulfur. So, is it that perchlorates are only slightly more stable then chlorates are when concerning sulfur?

 

I will dispose of the batch

[taiwanluthiers]

KP mixture does NOT need ball milling and it is strongly not recommended!

 

You don't really need to use KP for black match because its not going to offer any additional advantage compared to bp. If you have a hard to ignite mixture then prime the mixture where the fuse contacts the mixture so that it will ignite.

 

I have hit a mixture of chlorate and sulfur, only small amounts and its scary. They explode when initiated this way. I was told that perchlorate + S mixes are only slightly less sensitive.

Edited October 17, 2012 by taiwanluthiers

[fredhappy]

Kp mixtures are sensitive for friction and shock. That does not mean you can not safely work with KP. I have build scores of shells using KP coated ricehulls, I have had no problems whatsoever.. I made all my KP using an 80 mesh screen, and simply sieving the mixture 4 times . This can be done safely.

 

There is a diagram in shimizu´s book where he does drophammer tests with KP , and the mixture was surprisingly sensitive.

 

Problems can occur when you mechanically manipulate these mixtures, ballmilling being one example of this.

 

I´m glad my comment was of some assistance for you. Please be safe.

[FlaMtnBkr]

I have read a few times that it is suspected quite a bit of quickmatch from China is KClO4 based instead of nitrate. Not sure if it is true or an easy way to test for it, but it's not a new idea. I think people have made it for use with AP go getters, so that it doesn't get wet around the match from the formation of ammonium nitrate.

 

 

[chemtech89]

I appreciate all the comments. That was a big mistake on my part.

 

Follow up: When fully dried, I hammer anvil tested many small samples of the BM and all negative. In addition, the batch still has it going out issue when lit. when it burns (an inch) it suddenly goes out. It surprisingly does have a much harder time lighting ten typical BM. Because of this I felt comfortable enough to carefully make a 2' run of QM containing 4 strands. When lit, it quickly firecrackered 7" down the pipe and that's where it stopped. Disposing of the rest was done in a safe way and very nice too see. Not an ash left, completely consumed the batch.

 

And that's where this test will stop. I'm lucky i didn't hurt myself making such a stupid mistake.

Edited October 18, 2012 by chemtech89

[taiwanluthiers]

I guess you can test those bm with methylene blue. If it changes color it indicates the presence of perchlorate.

[dagabu]

The red QM I have shows a positive for perchlorates and works well for AP poured stars. It's readily available in the US and works very well.

 

-dag

[taiwanluthiers]

But I wouldn't staple them to set pieces... Some kind of tape or adhesive may be safer for that purpose.

[dagabu]

Staple guns are not legal for use in attaching QM in the US so thats not an issue.

 

-dag