Smokeless powder not explosive, blackpowder is?

What is the defintion of explode, what is going on that these things are different? How are other things, highly flamable things, classified. I have heard that gasoline doesn't explode, it only burns, is this true when it is vaporized?

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DO NOT TRY THIS AT HOME: Fill a bucket with gasoline. Fill another bucket with kerosene. Toss a match into each. Observe. Black powder is to gasoline as smokeless powder is to kerosene. Pick up some smokeless powder at a gun shop and light some on the ground. It kind of just whiffs up (technical term). However, put that same powder in a brass case stick it in a gun barrel...

The following is my opinion only. I am not a physicist or chemist and I didn't stay at a Holiday Inn Express last night.

Things that burn will all explode when put into a confined space. Smokeless powder in a spoon or on the ground burns. In a cartridge in the bore of a gun it explodes.

Explosions are identified by a loud noise while burning is not. Some things burn so violently even when not enclosed that they create a loud noise and therefore 'explode'. Blackpowder is an example.

Wikipedia:

Explosive Material
Should answer your question (yes I spend too much of my work day on THR and wikipedia...I know). More specifically the sections on Low and High Explosives.

Also if I remember my highschool chemistry properly (we actually watched a video on this if I am remembering right)....both smokeless and black powders are low explosives and thereby only "burn quickly" and only "explode" under certain conditions (being confined being one of them) and do not technically "detonate" ever even though they can be made to produce effects that very closely simulate "detonation". The wikipedia article can, I do believe, confirm this.

Blackpowder is an explosive.
Smokeless powder is a propellant.
They both will shove a bullet out a muzzle, but the chemistry is different.

As far as spikes of pressure, it's not only so much how high the spike is, it's how fast it's produced.
I'm not sure one is necessarily better than the other, but modern propellants generally contain more "umph" per volume and they do not produce as much fouling, which is really good when you're dealing with modern semiautos and other modern guns with closer tolerances.

An explosion is a unstable fast burn. It does not burn evenly. This is a common debate as to whether feul explodes or burns in a internal combustion engine. Powder burns quickly. This is what i was taught.

Unique and Blue Dot, both smokeless powders, are labeled by the manufacturer as "Extremely Flammable and Explosive".

You can shoot or burn a can of smokeless powder and it will not explode.

If you shoot or burn black powder it will explode.

I have done both.

When my gun shop burned the top or bottom of the smokeless powder cans just popped off.
The couple black powder cans exploded.

The center cans are smokeless powder.
The two burst cans on the right are black powder.
The burst can on the top left is WD40.

Hi Akodo

Smokless powder does not explode, it just burns. Blackpowder, on the other hand, actually explodes.

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From the standpoint of high energy chemistry BP does not explode as there is no "detonation zone" except under highly unusual circumstance. BP deflagerates or burns quickly. Smokeless burns slows but has a detonatation zone when ... detonated.

Look at it from this angle- Composition 4 when lighted with a match will burn slowly giving off great heat. Add a #6 blasting cap with a tetryl booster and it detonates at a rate (I think- it's been awhile) of 800 meters per second. C4, even with it's slow burn rate, is an explosive.

Next time someone tells you smokeless is not an explosive consider this. Bullseye pistol powder is 6 parts nitrocellulose and 4 parts nitroglycerine plus trace amounts of various stabilizing agents. That makes it a 40% dynamite no matter how you look at it.

(One of the persons that homeschooled me was a chemical engineer and a blaster.)

Selena

black powders are low explosives and thereby only "burn quickly" and only "explode" under certain conditions (being confined being one of them) and do not technically "detonate"

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Shoot a can of black powder and you will see this statement is wrong.
Using a .308 I shot a full one pound can and a can that had a half pound of black powder.
Both made a very impressive explosion and fireball. A detonation by anyone's definition.

I have also shot cans of smokeless powder. The cans may as well have been full of sand.

Basically the higher the compression the faster smokeless powder burns, place it in a pile outside someplace safe and light it and you will see a real nice flame just like a rocket engine, but no boom, you could not make a firecracker with the stuff if your life depended on it

Black powder's burn rate is the same for any F of powder, very fast in the open or enclosed, so you put a big pile in the same place and light it and boom, the only factor affecting burn rate is the size of the granule Example F burns slower than FF and FF burns slower than FFF, you get the direction I am heading here.
Which brings us to the point of the OSHA rule that almost passed on smokeless powder being total Bull, smokeless will not explode in the can period.

Put a table spoon of smokeless powder on your driveway and light it off, it tends to burn, rapidly, but you can watch the flame "spread".

Put a tablespoon of blackpowder on your drive way and it tends to go up all at once with a flash.

Is the above scientific, no, but it made the point to me.

Hi M2,

Right idea, wrong premise. When an nc/ng propellant is "loose" i.e. without close physical contact, the detonation zone is disrupted and a true explosion cannot occur. If you were foolish enough- or stupid enough- which I'm sure you are not... to dissolve the propellant with a suitable solvent then allow the solvent to evaporate to leave a solid block of propellant then use the proper amount of pressure (a high velocity bullet or primary explosive) you will get an explosion even without a container.

Selena

Unique and Blue Dot, both smokeless powders, are labeled by the manufacturer as "Extremely Flammable and Explosive".

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True, and you can make a pipe bomb from Unique. But it's not an explosive in the same sense that BP is. It's a propellant. In everyday use this comes up with storage and shipping issues.

You can certainly make smokeless into an explosive by changing its physical structure or by forcing it to ignite in a very compressed area with no release, but in the can it's not going to blow up. The factory containers are all designed to prevent the buildup of pressure, because smokeless gets more and more intense as pressure builds. This is why storing smokeless in sealed non-factory containers is such a bad idea.

True Officers'Wife.
The only point I'm making is that smokeless powder when burned or even shot is reasonably safe but when a can of black powder is burned or shot there will be a dangerous explosion.
Maybe not a maximum possible explosion but pretty impressive none the less.


As I recall those two cans of black powder in my fire were sitting on a shelf in the open.
I knew when each went off. The explosion was not what a pound of black powder is capable of but still scary.

From "Speer Manual for reloading ammunition" third printing May, 1962 page 20. article by B. E. Hodgdon "black (powder) is a low-explosive powder and should be respected as such. It burns just as fast without confinement as it does when used as a propellant.".....


Smokeless powder is progressive and confinement is necessary to obtain the characteristic of the desired powerful propellant.

Hi M2,

My bad, I was going by HEC standards and I see now the thread is legal standard. In the latter context, of course, BP is an "explosive" and smokeless only a propellant. Only in the minds of the great white father in Washington is a pyrotechnic mix more dangerous than a low velocity high explosive.

It's best I bow out now before I get into primary, secondary and tertiary explosives and velocity differences.

Selena

It's been a LONG time since I studied physics but isn't an "explosion" only a superfast burn rate? Technically don't all flammables, propellants, and explosives simply burn at different rates? As noted above, additional pressure can increase the burn rate of a substance/propellant.

Good shooting and be safe.
LB

an explosion is technically just something expanding really fast. black powder burns really fast, so it expands really fast. Smokeless powder burns slowly in the open, but in an enclosed space it burns fast, and expands fast.

Basically the higher the compression the faster smokeless powder burns, place it in a pile outside someplace safe and light it and you will see a real nice flame just like a rocket engine, but no boom, you could not make a firecracker with the stuff if your life depended on it

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Aah, but break open a firecracker and light the middle and you get the same "rocket engine effect." Unless, of course you stomp on it quickly. Then boom.

We did this all the time. Never wanted to waste a dud firecracker.

Smokeless powder in a spoon or on the ground burns. In a cartridge in the bore of a gun it explodes.

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It burns. When smokeless powder "detonates," it causes a severe pressure spike.

Modern smokeless powders are indeed "propellants". The point is not that they "explode", which they don't, but that they burn very quickly and produce enormous amounts of gas (which you can't see when you light it on a table). The gases, when confined by a cartridge case and a gun's chamber, force the bullet down the barrel and toward the target. When the rapidly expanding gases are released by the bullet exiting the muzzle, the pressure wave is perceived as a report.

Some powders burn faster than others. In a pistol, you want a fast-burning powder like Red Dot; the shorter the barrel, the faster the powder you need. If you have a lot of unburned powder residue in the barrel after firing, or a huge muzzle flash, your powder is too slow. A powder that is too fast, though, in extreme cases, can cause damage to the gun or even make it explode. That's why it's a very bad idea to use pistol powders in rifles.

Rifles need a slow-burning powder to make the pressure wave last as long as the bullet is in the barrel. If all the powder is burned before the bullet exits the muzzle, on the rest of its trip down the barrel the bullet is actually slowing down from the friction as the pressure curve drops off. This most commonly happens when a cartridge is underloaded--and the resulting low pressure as the bullet exits the muzzle is why underloaded cartridges aren't as loud. In extreme cases, the bullet will actually stick in the barrel, which can cause a subsequent full-power round to explode the gun. This often happens in pistols when a handloader tries to make low-power loads for a magnum handgun in order to reduce recoil and noise. I have personally seen a S&W .44 barrel sawn in half lengthwise to reveal six bullets lined up in the bore. If loaded with a full-power cartridge in this condition, the gun would have done a really convincing impression of a hand grenade.

Black powder works much the same way, but is a very fast-burning powder indeed, so fast that it is called an "explosive". Its burn rate can be crudely controlled by the fineness of the granules; the finer the grind, the faster the ignition. Thus, the fine-grained powder is used in pistols and the coarser-grained powders in rifles.

The chief advantage of modern powders is their stability. It's very hard to ignite smokeless powder without a primer, though an open flame will do it. I vividly remember watching my father stub out a cigarette in an ashtray piled with modern powder to illustrate that; he then touched a match to the pile, and it went up in a "whoosh" with very little smoke or ash residue.

Black powder, on the other hand, is scarily unstable. It can ignite (and when confined, that means "detonate") from static electricity, impact, or friction alone. More than one Civil War soldier was killed when his brass flask of powder blew up at his side when it was struck by a bullet--or while he was just running.

Many modern BP shooters prefer Pyrodex for that very reason--it's a modern compound that mimics the burning qualities of black powder, but is as stable and safe as modern powder. As a bonus, it leaves far less fouling in the weapon.

Hope this helped.

Static electricity will NOT ignite Black Powder. It is not a chemical compound, rather a mixture, and has no flammable vapors (no appreciable vapor point) to combine with atmospheric oxygen into a flammable mixture. Carbon is a great conductor of electricity, to boot. More energy needs to be supplied before the powder will self-ignite.

Static electricity has basically no current. I've tried to get it to ignite with a spark, no dice. A MIG welder WILL ignite it, but that's a heck of a spark (with lots of heat produced)

This guy has also tried it:
http://www.ctmuzzleloaders.com/ctml_experiments/sparks/sparks.html

This is just a ridiculous matter of semantics.

The definition of explode:

to expand with force and noise because of rapid chemical change or decomposition, as gunpowder or nitroglycerine

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Both black and smokeless powder fit that description.

OK guys, do me a favor and find a copy of Tenney's "Chemistry of Powders and Explosives." It will ease your minds quite a bit and relieve you of a lot of misconceptions many of you seem to have. Don't let the title throw you, the math is minimal and gives a great deal of information on the subject of BP and other pyrotechnic mixtures as well as their properties.

Another reference though more concern with manufacture is Weingards' "Pyrotechnics." Although it goes into great detail on the office of surface area to pressure. Again the math is minimal and the writing is presented in such a way to be interesting.

As for smokeless there is a military training manual from the 1940's called "Military Explosives" that not only defines detonation v deflag but describes in detail the diff between the detonation of a high explosive and a so- called explosive mixture. However, I don't reccomend it for light reading.

Item last... The "carbon" in BP is charcoal. Charcoal is NOT repeat not a good conductor of electricity. It's the sulphur in the mixture that lowers it's flash point. Static discharge "can" cause the stuff to flash but not necessarily will. When pyrotechnians build devices (such as Roman Candles) they wear a grounded cuff on their arm to prevent static discharge. Of the pyrotechnical compositions Nitrate based mixtures (such as BP) are considered the safest to manufacture.


Selena