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Ken Hansgen, 11094
03-22-2011, 09:28 PM
Dave, while replying on another thread, recently reported that an electrical engineer told him he had had an accident while pouring powder into a container. He or Dave theorized that was due to static electricity. I said I was concerned because I do that often--when I finish a loading session I pour the unused BP still in my measure though an aluminum funnel back into a 1# can that usually has more BP already in it. I asked Dave if he knew whether that was dangerous. Maybe he'll answer here.

Timmeu
03-22-2011, 10:00 PM
HI

I am no engineer but I use plastic funnels from RCBS for the very reason you mention.

Timmeu

Ken Hansgen, 11094
03-22-2011, 11:12 PM
And I've been told that plastic is more likely to build up static than aluminum Perhaps RCBS has added something that prevents this?

DAVE FRANCE
03-22-2011, 11:48 PM
Ken,

He is an engineer, and I think he is an electrical engineer.

I will ask him for details and I will ask if I can put his name on this BB.

I am glad you wanted more information. Let me put some background information here.

1) There was a test done and showed on the internet, and reported in the skirmish Line. It showed electrical sparks hitting a small pile of black powder and the powder never caught fire. I think the reason given was that the powder never got hot enough to catch fire because BP is too good of a conducter to get hot. That makes sense to me.
2) BP will ignite without a spark, just from heat. And I think the ignition temperature is less that 500 degrees F. If you took a nail and heated it up to red hot, it will ignite BP without a flame. If you let the nail cool off, it will still ingite BP until the nail temperature gets below the ignition temperature (less than 500 degrees).
3) A spark will ignite BP if it is above the ignition temperature. Sparks from a flame, a cigarette, etc. will ignite BP. Two people I know were burned because of smoking near BP or shooting near an open container of BP. There was an accident in Michigan (not at an N-SSA event) that killed several people in the 1960s. I understand that it was caused by a spark or floating ember that fell into the powder storage container.
4) Several things can blow up while in a powder or dust form in air. They can explode from a spark (including a static spark) or from contacting something that is hot. I looked up informationa bout this some time ago, but I am no expert on this and may have something wrong. My recollection is that the dust must be at a high level concentration to explode from static electriciy. Many types of plants or storage facilities can have explosions. I think rice, wheat, and sugar are liable to explode under the right conditions. And these types of explosions occur fairily often.
5) I worked in an ammunition plant in part of 1966 and 1967. I was the production engineer for F - Line, which was actually one of several plants in the plant. Louisiana Army Ammuntition Plant where BP is made now. To access some parts of the plant it was necessary to wear conductive soul shoes to prevent a static buildup. One part of F-Line was a melt building where explosive was brought in and melted, and then poured into small (soft ball size) cluster bombs. One of the things I did while there was improve the ventilation system to keep the explosive dust level low. The plant seemed to think that static sparks could cause an explosion.
6) I was drafted In September 1967. I skipped part of Basic and was sent to an Army Ordnance facility. The next year, the melt building of F Line blew up. It left a big hole in the ground and killed everyone in the melt building. F-Line was closed permanently. One of my uncles worked in another part of the plant and he said it was a terrifying experience. I think the explosive used in the bombs was not something that is easily ignited. I think most explosives used by the militay then had to be exploded by a smaller charge, that caused the main explosive to explode.

7) By a strange coincidence, my mother worked in an ammunition plant in Nebraska in 1944 or maybe 1945. She worked in the melt building, but when my father came back from some training and found out he made her quit. The next week the building blew up and killed everyone there.
8) I am sure BP will blow up while in a powder form in the air. And it will probably do it from a static spark. when I saw the information about the sparks hitting the pile of black powder pile, I thought that could cause some confusion that might lead to someone being careless and result in an accident. But probably it would have to be a heavy concentration to explode while in powder form.
9) Last item. While I was in the first grade, a friend of mine who lived less than a block from where I did, lost both his hands. He picked up blank 22 rounds that the pirates dropped in the Gaspirilla Parade in Tampa. I don't know exactly what he did to cause the accident, but both his hands were burned very badly. He probably emptied the powder from the blanks and lit it. That was in Tampa, Florida in 1947 or 48.


All this is from my aging memory, and I am not an expert in BP or explosives.

Good luck!

David

R. McAuley 3014V
03-23-2011, 12:07 PM
Ken,
1) There was a test done and showed on the internet, and reported in the skirmish Line. It showed electrical sparks hitting a small pile of black powder and the powder never caught fire. I think the reason given was that the powder never got hot enough to catch fire because BP is too good of a conducter to get hot. That makes sense to me.


http://www.ctmuzzleloaders.com/ctml_exp ... ricml.html (http://www.ctmuzzleloaders.com/ctml_experiments/electric_ml/electricml.html)

It’s rather interesting that the author of this article describes how in his earlier experiments in attempting to ignite black powder failed because he had not used sufficient current, so in this subsequent article describes how in performing other experiments:

http://www.ctmuzzleloaders.com/ctml_exp ... parks.html (http://www.ctmuzzleloaders.com/ctml_experiments/sparks/sparks.html)

“I had measured the resistance of a lightly packed pile of black powder and found it to be about 1000 Ohms. When you apply a voltage to something that conducts, current passes through it and some of the energy is dissipated as heat. The formula for this is:

Power (watts) = Voltage*Voltage/Resistance.

If I put 100 volts through that pile of powder, I get a power dissipation of 100*100/1000, or 10 watts. It's not much, but in a tiny pile of powder, the heat builds up and will ignite it almost instantly. After playing around with it a bit, I decided to use about 200-300 volts to ensure almost instant ignition.”

How then could 200-300 volts of electric current “ensure almost instant ignition” when according to his previous article, when he had applied 10,000 volts had failed to accomplish the same result. So what's that stuff they coat black powder with so as to reduce friction and static electricity? It's graphite, isn't it? I wonder whether being coated in graphite might have something to do with delaying black powder kernals from heating up until the reach their autoignition temperature?

DAVE FRANCE
03-23-2011, 01:34 PM
It seems like for the pile of BP there was no complete electical circuit to allow current to flow. For his rifle, he had to contacts that contacted the cup with powder in it. And there was a path for the current through the powder in the cup. I did not read his paper carefully, and I may have missed something.


David

Ken Hansgen, 11094
03-23-2011, 03:11 PM
That's all very nice, but just remember that we "commoners" are seeking practical advice. Seems like Goex is dustier that Swiss--does that mean it's more explosive? What can we do in our loading area to reduce the risk of static buildup? Is plastic riskier than aluminum? What does RCBS do to their plastic funnels (if anything) to recommend them for BP? Is there a practice I should avoid? Stuff like that.

DAVE FRANCE
03-23-2011, 03:19 PM
Pour slowly. Don't pour near a flame or anything hot. Pour where there is good ventilation and where the powder that gets in the air does not build up. Read what is on the internet about explosions in flour silos, ect. if you want to know more.

David

Jim Brady Knap's Battery
03-23-2011, 04:12 PM
It might be good to do as we always did in my aviation carreer when fueling aircraft. To avoid the chance of static sparks with aircraft we would ground the fuel truck to the earth and airframe and the fuel nozzle to the airframe. Perhaps keeping physical contact with the item pouring from, the funnel, and the item being poured into would help avoid any static charge developing that could cause sparking.


Jim Brady
2249V
Knap's Battery

R. McAuley 3014V
03-23-2011, 05:26 PM
You gents seem to have missed the point. The granules or powder kernels of black powder, as well as smokeless powder, are often coated with graphite as a lubricant to prevent the build-up of static electricity as well as act as a burn moderator. Synthetic graphite is made from anthracite coal and is an excellent conductor of electricity, allowing the static charge to pass from particle to particle eventually discharging harmlessly to a grounding source. The fact that the graphite (carbon) coating also helps round irregular edges of the propellant increases its surface area and acts as a heat sink preventing the build-up of heat from entering the granule, which, if otherwise uninhibited, would allow it to reach its auto-ignition temperature and self-combust. So certainly the rougher you handle a propellant and injure its lubricant coating the greater the likelihood that some injured particles may more quickly self-combust and thus contribute to the explosive train with the remaining propellant. However, it should be emphasized that some manufacturers, such as Swiss, supposedly don’t use graphite as a lubricant so may be more unstable than other brands. According to Owens Compliance Services (representing Goex), graphite is not contained in all grades of black powder. So be careful when handling your powder.

Joseph Plakis Jr, 00302V
03-23-2011, 05:47 PM
I would like to make one point about that plastic can cause an explosion with black powder.
I have been buying black powder (Goex) since it has been for sale at the nationals. I would like to point out it comes in a cardboard box with the "black powder" in a "plastic bag"!!
I would think that the Goex people have an insurance agent that would have a fit if he knew Goex was in a container that will cause a spark and an explosion!
I don't think it is a problem. If it were a problem the black powder would not be in a "plastic bag"!

Joe Plakis Jr
Hampton Legion 00302V

DAVE FRANCE
03-23-2011, 05:59 PM
Jospeh,

Good comment about plastic packaging. But, regardless of what the container is, it isn't wise to pour a lot of powder and raise a cloud of powder in the air that might explode, just as happens in wheat silohs.

If I can find out more about what happened I will post it. If I can't I will let you know.
David

Charlie Hahn
03-23-2011, 06:47 PM
I would like to offer some basic information based on training I had in a past life working with Class A and primary ignition devices.

First Plastic, they are all not created equal. I think you find where manufactures use plastic in conjunction with Class A Explosives is conductive to some point where it is limited in it's ability to hold a static charge.

Other items, all tools used when handling black powder should be conductive and non-sparking, that means brass, aluminum, zinc, lead, and some plastics with carbon in the mix and check with an ohm meter, (remember goex cans are black plastic).

General handling, you should never hand an open container of Class A powder to another person. It should placed on a conductive surface that both are grounded to, this way all three are at the same potential. When the powder is in a sealed conductive container this potential in minimized due to the fact that the container acts as a faraday cage, but in a working area, the possibility of residue is possible, so sit it down and let the other pick it up.

Working, keep the quantity low, and unused powder away from where you are. If there is a fire, and least you should only be burned and not hurt worse. I know it is a pain to move to get more when its late and you have a bunch to load, but no short cuts. Stand up walk and get it, stretch, breath, resume.

I saw the article about the static spark not setting off the loose powder, and it is of grave concern to me. First the demonstration is questionable, and in a certified testing facility would have been done remotely with written procedures and managed by a controlled firm that would have published some report, so I see this as a stunt rather than some credible safety test. Sorry for this comment, but I visited the crater noted above while spending time on a melt pour line, and I take handling these materials very serious.

In closing, we have to remember we all handle Class A Explosive. It is used as a primary explosive in very complex systems. I worked with loading room limits of less than a pound, and passed through a wall. Our safety officer would remind us daily, "you are working with reactive material, and sometimes it will".

Keep the quantities low in the working area. Make your loading bench with an aluminum surface that all your equipment, the powder and you are connected to. Loading the final round is not a spectator sport, keep people and distractions to a minimum. Make sure your funnels, and other items are conductive and of non-sparking material, Aluminum and brass are the best.

Regards,

Charlie Hahn

DAVE FRANCE
03-23-2011, 07:42 PM
Very good Charlie!

David

Ken Eckard
03-23-2011, 09:30 PM
Hi Guys,,All of this sounds great and a big thanks for all the info,,,especialy about reactive ,,and Class A explosives indeed! Safety sometimes is ignored (ignorent) while handling this seemingly harmless material, I was just wondering what our friend and neighbor Jack Venskosky would say along with all your comments . All info Good no matter how simple. Makes me wonder about the plastic bags he puts 5pounds in inside paper bags??
Ken Eckard
1stMDCavCSA

Eggman
03-23-2011, 11:33 PM
I used to work with a fellow who was once employed by the Rock Island Armory manufacturing artillery. Most artillery projectiles contain a black powder booster. He said black powder dust would accumulate among the rafters over time and periodically "flash" scaring the hell out of everybody. Static electricity was the only explanation. We all know how common plastics can accumulate a negative charge, so all plastics spook me. That static charge likes to jump. I am in awe of smokeless powder sold in plastic containers. That said I am sure GOEX knows for sure that their 25 lb. plastic powder bag won't accumulate extra electrons (???).
I always try to remember to "ground" myself with my other hand before picking up any black powder container. ANY black powder container.
But all that said, our greatest danger is still that smolder in our guns we pour fresh powder on; and that loose powder we spilled on our work bench and didn't bother to clean up.

Michael Bodner
03-24-2011, 04:14 PM
The plastic bags used to store the powder are conductive. Tey will not permit the build-up of a static charge. Same stuff used for electronics to prevent damage by static electricity (ESD).

So, not all plastic is bad.

-Mike

Southron Sr.
03-24-2011, 04:53 PM
I remember seeing the news report of the Michigan accident BACK IN THE LATE 1960'S (?). It actually made the Walter Conkrite News broadcast. The news story,as reported by Cronkite, didn't show the explosion-only Skirmishers shooting in a musket team match and then the aftermath of the explosion.

My understanding (based on information I learned years later)is that during an artillery match a spectator wandered behind a gun crew and balanced a lighted cigar on the edge of an open ammunition cassion. The cigar fell into the box and KER-BOOM! Supposedly the cigar smoking spectator made a 'dying declaration' about placing his cigar on the lip of the casson in the hospital shortly before he passed away.

In another incident, I know an individual in Statesboro, Georgia that claimed he simply picked up a brass flask full of black powder and it went off in his hand! He attributed the accident to the fact that he walked across a carpet in his socks and this somehow built up a static charge in his body. I don't know whether to believe him or not.

One Fall afternoon about 5 or so years ago, my son and I were installing a Satellite Dish on a house in the country on the East side of Eatonton, Georgia. We both heard an explosion in the distance. My first impression was that someone's propane tank had exploded.

What happened was that a man that had a custom ammo loading business was killed in an accidental explosion. He had a small building, in his backyard, not too far from his rural home. He custom loaded black powder cartridges such as 45-70's, 50-70's etc for the Black Powder Long Range shooters.

The explosion totally destroyed the building (leaving a crater in the ground)and at the time the custom reloader was inside of it loading ammo. It was known that he kept a large quantity of both black and smokeless powder stored in the building.

One speculation was that perhaps he had accidentally discharged a gun in the building and the bullet struck one of the containers of black powder. No one will ever know what happened for sure. One of the Deputies that responded told me that what was left of the reloader's body was found over 100 feet from where the building had been located.

Here are some basic "Common Sense" rules:

1. When loading black powder cartridges, have only a small quantity of black powder on hand-the rest of your powder should be stored far away as possible.

2. DON'T SMOKE WHEN LOADING OR HANDLING BLACK POWDER! There have been several major accidential explosions traced to someone smoking around black powder!

3. Pay attention to what you are doing. Don't let your mind wander because that is when mistakes are made.

4. Use only "non-sparking" reloading equipment. There are several companys that manufacture and sell reloading equipment specifically designed for black powder.

5. Always wear SAFETY GLASSES when reloading.

DAVE FRANCE
03-24-2011, 05:19 PM
Southron,

Two people who were there, told me(at different times) that it was not an N-SSA event, and the cannon shooters were members of a motorcylce club putting on a demonstration.

David

DAVE FRANCE
04-05-2011, 06:01 PM
More information about the black powder accident that is the subject of this series of messages.

I talked to Bryan Buck today. He is the person who told me about an accident with blackpowder which injured him. He confirmed that the accident occurred while pouring black powder and that it was caused by a static spark touching off the BLACK POWDER DUST that occurred while he was pouring the powder.

Bryan just retired as an electrical engineer and he is a DISTRIBUTER FOR CIMMARON in North East Texas. He also is a gun collector and a gunsmith.

If someone wants to ask him what happened and put his reply on the BB I'm sure it will be interesting to our members.

David

DAVE FRANCE
04-05-2011, 06:05 PM
I forgot to include Bryan's email address.

It is btbuck@embarqmail.com

David

Eggman
04-09-2011, 10:29 AM
Go to homemadegunpowder.wmv

DAVE FRANCE
04-09-2011, 11:50 PM
Eggman,

There is something in Hatcher's notebook about some people gathering to see a large pile of propellent that was to be set off. He said in his book that they moved far enough away to feel safe, but when it was ignited people were burned fairly badly. This is from memory, so I may not remember it accurately.

David

Rtab108
04-10-2011, 09:30 AM
Dave, Your comment soundsas if you think that Jadkie Venskoske puts the powder into plastic lined paper bags. I'm pretty sure that That;s the way it comes packaged from from Goex Bob T 108th NY

DAVE FRANCE
04-10-2011, 09:54 AM
RTAB108,

I haven't commented on that at all. Even if he does pour powder from a larger container into a bag, he must know what he is doing.

David