Explosive vs Gunpowder

Jimro,
Now you are getting into an area I'm intimately familiar... 16 years worth.

That C-4 will explode while burning is a myth, tried it many times.
I understand that early C-2 could be detonated while burning,
But C-3 & C-4 require MUCH higher compression rates to detonate than a human can produce.

I've seen tracer bullets pass through C-4 many times.
(Yes, bored Marines will shoot at C-4)
C-3 & C-4 was specifically designed to go into combat,
While stuff like RDX & PTEN won't take rifle rounds very well.

Mix RDX & PTEN (and a couple other things) and you come up with 'Home Brew' Simtex, a favorite of our suscide vest wearing 'Friends' in the sandbox.
They USED to go with plain old C-3 or C-4, but you could shoot through without detonation to stop the idiot,
With the home cooked simtex, you have to have a headshot or risk detonation.

The stuff a farm kid learns when he sets out to 'See the world'...
 
The easiest way to consider the question is to accept that under normal circumstances, with ordinary quantities, used properly, smokeless is not a high level explosive. It has been around for over a century, and for most of that time it wasn't scientifically proven to be possible.

For shipping,It's regulated as division 1.3 explosive and referenced as not having a mass explosion hazard. It is regulated with professional grade fireworks and rocket fuel. 1.4 is consumer grade fireworks and ammunition, black powder is 1.1, they differ in sensitivity and capacity for a "blast" or "explosion".

Class 1.1 includes black powder and nitroglycerin, presenting a "mass explosion hazard".

Class 1.3 includes smokeless and it is a "minor blast hazard".

Class1.5 includes unaltered ANFO.

Way back before regulations were strict, a story goes that many, many tons of smokeless was contained in a magazine at a plant surrounded by a berm, and it was accidentally set off. The berm wasn't damaged, the building remained mostly intact, there were no injuries as the area was unoccupied, but it created a flare and flame that could probably have been seen from jupiter.

So by classification it is called an explosive, it's regulated as a blast hazard, but not an explosion hazard. Although it is compounded with high explosives, just like dynamite is, inhibitors and stabilizers change those characteristics. Dynamite is ng mixed with essentially dirt and that prevents the ng from igniting with shock or flame, it shouldn't detonate unless an extreme shock sets up the proper conditions. Powder is compounded with other chemicals meant to prevent the ng from igniting in a chain reaction that results in an explosion.

The way I see it is that it is, by definition and legal definition, an explosive, a class 1 substance. It is not a class 1.1, the highest level, it is considered a class 1.3, which does not cause an "explosion".

Think about it this way. The high explosive compounds in smokeless is in isolation, with buffers in between the molecules and powder grains. Even though fireworks are clearly made out of class 1.1 products, these products are buffered by packaging and other inert products. They are capable of a chain reaction blast, but not an "explosion".
 
JeepHammer,

Shooting C4 won't detonate it until you shoot with something like a Raufoss API round from a Barret, where the disintegrating zircon ring provides it's own little explosion providing both heat and pressure to start the detonation sequence. Sometimes when you try to start C4 with detcord the detcord explodes so fast it can "cut" the C4 before it detonates, and you find chunks of C4 all over the demolition range...

Burn it on hard concrete, and drop an anvil on it, odds are you'll get enough to detonate. I'd say a Marine's boot probably wouldn't do it, probably need a Sailor, of at least Senior Petty Officer rank to get enough mass (I kid, I kid).

But the point is the same, you can get it to blow up with a commercial/mil grade blasting cap, as it can both deflagrate and detonate. Some explosive just don't deflagrate like Lead Azide or black powder and only detonate.

Jimro
 
Explosive is a relative term. Its nothing more then burning, but at a faster rate.

For example a low explosive would be somewhere near 14-16000 fps, where as a high explosive it closer to 26-27000 fps.

(Those are not hard and fast numbers, just thrown out there for references)

Meaning, Rate of Burn.

Basically there are two types of gun powder. Double based and single based.

Double bases contains Nitroglycerin and Nitrocellulose. Single based is Nitrocellulose. The size of the powder pieces and additives determine the burning rate.

Both are considered explosives, However you control the rate of burn, they are used as repellents.

Burning rates are regulated by heat and concussion. You just add head to the explosive, you get a slow burn. You add concussion with that heat you get an dentation (much faster rate of burn or explosion.

You can light C-4 on fire and cook you C-Rats, but you strike that burning stick of C-4 you get a much faster rate of burn, or an explosion.

Same with gun powder. Both Nitroglycerin and Nitrocellulose are explosives, but you control or restrict the rate of burn its a propellant.

With C-4 (and other explosives) you can burn it, or you can set if off with a blasting cap and it will explode (or burn super fast).

Same with smokeless gun powder, you can light a match to it and it will burn, You stick a blasting cap to it, it will explode (or burn super fast). It then becomes an explosive instead of a repellent, which is nothing more then a much faster rate of burn.

Depend on the make up of gun powder, (additives to control the rate of burn) you may need a stronger blasting cap, or a buster, but it will explode.

Basically repellents and explosives are nothing more then a difference of rate of burn. You control the rate of burn you can convert an explosive to a repellent to an explosive or visa versa.
 
Basically repellents and explosives are nothing more then a difference of rate of burn.
Click to expand...

I'll be much more careful how I handle Deep Woods Off and Cutter's in the future.;)

That and the earlier comment by ShootistPRS separate detonation and confined explosive deflagration from open air deflagration, but not explosives from things that cannot explode. Exploding or deflagrating are both forms of combustion (burning), just different mechanisms. The former causes energy release by heat transfer and the latter by kinetic pressure wave. The former travels at the rate of heat transfer and flame spread, while the latter travels at the speed of sound in the explosive material or a bit faster due to compression. But as already remarked by several of us, many high explosives can either deflagrate or detonate depending on the source of ignition energy.

PETN (pentaerythritol tetranitrate) has been used as the igniter in incendiary rounds. So it can withstand acceleration in a gun barrel but not impact with anything very hard without going off. It is also the ignition charge used in the old standard powder burn rate test.
 
Do we count Mythbusters who did a couple of segments trying to detonate C4?
They shot it with bullets, stomped it with a boot while on fire as to put out a cook fire, dropped a skillet on it as at a cook fire, etc.
Nada.
Insert blasting cap, BOOM.

There is a local legend that some of the good old boys inserted a blasting cap into one of the old cubical Bullseye (40% nitroglycerine) cans and got it to go high order, pulverizing the stump the can was set on. But I wasn't there.
I do not discount the possibility, the British used Cordite for demolitions.
 
I don't believe the old legend, I don't guess that you really do, either. Nearly 100 years of solid scientific research has come up over and over saying that you can't set off a can of gunpowder like a stick of dynamite or other high explosive just by capping it. I'm not even sure that a can of super coarse black powder would go high order if it was capped, unless that can was made of welded steel. The stuff ought to be just sprayed, a cap isn't strong enough or hot enough to set up the sort of shock and heat needed to detonate a compounded explosive.

Black powder, the fastest burning powder, still burns slowly. Black powder fireworks stars don't detonate after high level explosives blast them out of commercial canisters. They are made out of powder and metals bound with starch.

There's a legend around here about a great big smelly hominid that steals food and liquor from campers.

I wish that I could have cited all the information I posted. I'd love to see some reliable citations for some of the things that are posted here.
 
So what would you expect to happen if you had a pound of Tannerite attached to 100 pounds of black powder? Could the Tannerite serve as an adequate detonator?
 
I would expect an aerosol detonation using tannerite under black powder. About the same thing as a gallon of gasoline over a pound of black powder.
 
As I mentioned earlier, dividing an explosive into grains mitigates the chance of detonation. This is because a bunch of little grains only contacting one another at small points can't conduct a shock wave well. Make the same material in a large, solid block, then you'll have another story.
 
Black powder, according to some reliable sources, is known as a low order explosive. The burn rate is subsonic and a high explosive burns at a supersonic rate, or detonation.

Black powder cannot be correctly said to detonate, the carbon nitrates, and sulfur have to combine, that is a slow process. High explosives are sometimes complex chemicals that break down into simpler components, breaking down with incredible speed, nearly instantly turning a mass into heat, and concussion.

Black powder is effective with containment and compression. A plastic canisters of bp will mostly burst and burn. A pressure cooker bomb made with fireworks powderwill rapidly build up pressure and violently explode, but that isn't technically detonation. A true high explosive isn't relying on pressure, the detonation will cause a shatter effect as well.

This subject is so full of words with multiple meanings with varying context, so many complicated nuances.

One of the most fundamental questions is whether or not the compound can burn through at a supersonic rate, and even though most high level explosives can be burned at lower speeds without exploding, they can and will detonate easily when hit with extreme force and heat.

A good example is tannerite. A .22 won't detonate it. A subsonic slingshot can't. It requires a heavy physical shock that can hammer the molecules at high speed.
 
Nick is absolutely right. A major reason and explanation is that the shock wave and flame front must travel at greater than Han the speed of sound, and in a solid, compressed block, every molecule is in intimate,
Contact, those compounds allow the front to burn on uninterrupted.

Beads, flakes,pellets,every fragment must individually start combustion, ignited by the firs one. Even though each particle "detonates", each one must be fired by the previous explosion ..a string of explosive beads, an air gap of 1/8 inch between them may even be visible as the explosion progresses, and adding compounds to keep explosive compounds in a blend, separated, prevents "detonation" velocities from being achieved.

This is why it is so unlikely that a can of bullseye could "detonate". The explosive compounds are separated and buffered at nearly the molecular level. The grains create air gaps that must be crossed. These problems prevent the burn front from going supersonic. No matter how much ignites, that flame must still progress quickly enough to ignite The individual grains, and the flame and concussion must be so powerful that it forces those granules to instantly collapse, rather than burn at the expected controlled rate.
 
Shooting, I did, it didn't work, there was no internet, and a black powder charge didn't work. It was a stupid plan.
 
Good Lord, I'm tired. I need to let this go.

I hope that it has helped. I've researched everything carefully, and I hope that I haven't committed any seriously mis-communications.
 
ShootistPRS,

There is no contradiction. What I said is the granulation mitigates detonation. It doesn't necessarily stop it. That is material and mass dependent and is affected by how plastic and sensitive the material is. But in nitrocellulose and double and triple base powders, granulation works pretty well until the quantity gets huge.
 
I agree when talking about smokeless powders. I know for a fact that a pile of black powder detonates. It is ignited by the shock wave moving through it. Black powder is a primary explosive and will detonate with pressure or heat. It doesn't "burn" as fast as high explosives but you don't see the flame travel through it either.
 
You can wet it and press it into large cakes. That's actually done as part of the manufacturing process just before the roller mills break it up into grains. It makes for a huge, slow burning powder grain, but a collection of those would definitely detonate more readily in the presence of an explosive able to create a potent enough shock wave.
 
Shootist:

black powder is a low explosive... low explosives deflagrate at subsonic speeds and high explosives detonate at higher speeds creating a supersonic wave...
Click to expand...

Black powder explodes, but it does not detonate. There is a difference. Black powder is a schedule 1.1 high order explosive because it is stable but easily ignited, especially in fine particles, and it burns rapidly and uncontrollably, causing a risk of dangerous explosion, but not a detonation. Nothing can cause it to detonate, but many things cause it to catch fire and burn with the combined fuel and oxidizer. It is sensitive. It has even been known to explode from static shock from clothing.

This can all be found in many different resources, Wikipedia is reliable and has detailed information provided and approved by experts in many fields.
 
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