Gunpowder

[Eutycus]

We are discussing Western Movies on another forum. Two of the John Wayne/ Dean Martin movies were mentioned. In "Rio Bravo" thrown dynamite is detonated by shooting it. That can't happen, it takes blasting caps. In the movie "The Sons of Katie Elder" a can of gunpowder is set off by a gunshot from John Wayne. Could that have happened?

 

[longcruise]

In the movie "The Sons of Katie Elder" a can of gunpowder is set off by a gunshot from John Wayne. Could that have happened?

Yes, at a shoot back in the early '80's we shot a full can of goex. We just all shot at once. It went off!.

 

[Eutycus]

Yes, at a shoot back in the early '80's we shot a full can of goex. We just all shot at once. It went off!.

One theory is that the bullet piercing the metal can produced sparks. Could a lead bullet produce sparks? I seriously doubt there would have been enough heat from just the bullet.

 

[Tumbledown]

We are discussing Western Movies on another forum. Two of the John Wayne/ Dean Martin movies were mentioned. In "Rio Bravo" thrown dynamite is detonated by shooting it. That can't happen, it takes blasting caps. In the movie "The Sons of Katie Elder" a can of gunpowder is set off by a gunshot from John Wayne. Could that have happened?

Dynamite can indeed be set off by gunshots. Even some modern explosives can be. It all depends on the initial amount of energy it takes to set it off.

As for the can of powder, it depends on the heat generated from the bullet's friction/compression.

 

[Eutycus]

Dynamite can indeed be set off by gunshots. Even some modern explosives can be. It all depends on the initial amount of energy it takes to set it off.

As for the can of powder, it depends on the heat generated from the bullet's friction/compression.

I was under the impression it took a blasting cap to "set off" dynamite. Is it the heat from the bullet that does it or the actual impact?

 

[Thingamajiggy]

I've seen slo-mo videos of small explosions and what appears to be a spark with bullets striking Balistic gelatin. Maybe it has something to do with the same principles? Not sure if all lead muzzleloader bullets could produce such phenomena since it says it's due to the rapid expansion of the bullet but is interesting none the less.

hackaday.com/2016/10/13/watch-the-diesel-effect-in-ballistic-gelatin/#:~:text=After the expanded bullet exits,flash followed by some exhaust.

 

[Eutycus]

Is it true dynamite will burn?

 

[snakebit]

There is an ATF agent somewhere screen shoting this

 

[Eutycus]

There is an ATF agent somewhere screen shoting this

I have no desire to set off any explosions, I was merely asking. We were discussing the authenticity of some Western movies. Hollywood does tend to take liberties,as you are well aware of.

 

[waksupi]

We used to shoot a lot of dynamite. It has to be 60% or more to go off on impact. Nitroglycerin works! We can't just go to the lumber yard and buy it anymore, have to get a permit from the sheriff's office now.

 

[Eutycus]

Again with authenticity, when was Nobel's invention of Dynamite? Those aren't powder sticks that Eastwood is using in some of his movies.

 

[Historian]

Looks like he did it in 1867.

 

[waksupi]

Is it true dynamite will burn?

Yes.

 

[Robert Losekamp]

I was under the impression it took a blasting cap to "set off" dynamite. Is it the heat from the bullet that does it or the actual impact?

If the dynamite is improperly stored it can sweat nitroglycerin, which is an extremely dangerous and unstable explosive that can be set off upon impact.

Adam Savage did a test on it with just smacking a puddle of it with a hammer:

 

[Eutycus]

Okay that was pure nitro . The original question asked if a stick of dynamite would explode if hit with a bullet.

 

[david w]

Okay that was pure nitro . The original question asked if a stick of dynamite would explode if hit with a bullet.

I don't know about dynamite in general, but when I was a young boy, my dad and uncle was very concerned a few sticks had what they called "sweat". They said it was very sensitive and made me get the hell out of Dodge. The lot was later detonated safely.

 

[Rancocas]

What about propane? What if you shot one of those small propane bottles used in a camp stove?

 

[pilot]

What about propane? What if you shot one of those small propane bottles used in a camp stove?

You will puncture the tank. It won't ignite without a flame or spark nearby.

The real fun starts when you toss one in a campfire. The safety valve is designed to vent the tank, but if the vessel fails, you get what is known as a BLEVE. Boiling Liquid Expanding Vapor Explosion. It doesn't really "explode", but the results are similar.

 

[waksupi]

Okay that was pure nitro . The original question asked if a stick of dynamite would explode if hit with a bullet.

asked and answered.

 

[Loyalist Dave]

Okay that was pure nitro . The original question asked if a stick of dynamite would explode if hit with a bullet.

So dynamite and TNT are two different things, but information about TNT tends to be confused with dynamite. Original dynamite was 40%-60% nitroglycerine, combined with diatomaceous earth. What this did was to drastically reduce the chance that the nitro would explode while handling. Reduce..., but not eliminate...

BUT..., original dynamite (invented in 1866) has about a 1 year shelf life. It must be kept cool (which is why you see movies where folks boil it to extract the nitro) and it must be rotated often to keep the nitro from seeping out of the sticks due to gravity. Even when properly handled, a slug from a Winchester could very well set the stuff off.

Now out West, the stuff probably took a while to arrive at a frontier destination, and then if it was stored too long, even with proper handling, its level of stability would degrade. Eventually, original dynamite would be difficult to prevent it from going off by accident.

TNT is used by the US Military and not dynamite, because it's more stable than dynamite, and does need a good initiator to set it off.

LD