powder in the pan ignites powder in chamber

[Dude]

Thank you for asking the question, Greg. This has been fun and I've learned something. It's been proven now to my satisfaction it's not sparks or burning powder contacting burning powder in the chamber that sets off the charge, but either a heat or flame front. Also, the longer I'm around you guys the more interested I've become in flintlocks.

 

[ApprenticeBuilder]

Interesting thread with some downright funny assumptions,

It is amazing how many wives tales are dismissed with a series of scientific experiments conducted at 5000 frames per second, thanks again Larry Pletcher for bringing science instead of emotions to flintlocks and how they function.

 

[ugly old guy]

It's the hot gas from the priming pan going off that ignites the main charge. That's why old timers fill the pan at most half way, and then cant the gun and tap it a few times so the powder in the pan is away from the touch hole once the fizzen is closed. If the pan is full to make a "fuse", you add a few milliseconds to the ignition time. So "they" say...

Actually, they tipped the gun lock angled up so when they tapped it, part of the 4F or 5F priming charge could enter the vent, making a direct connection to the main charge.
If no priming charge was used, such as during a skirmish or battle, they tipped the gun lock angled down, so when they tapped the gun the smaller granulations and dust of the main charge went into the pan.
Filling the pan half way was a means of conserving their powder. It don't take a full pan to set off the main charge.

 

[flashpoint]

OK, here we go.. How high does the temperature of radiant heat have to be in order to ignite the charge?

 

[Omhra]

If the flint is creating the spark then why does the frizzen need to be a steel with a high carbon content not just hard?

With no powder in the pan why do you have small pieces of steel remaining after multiple sparkings of the lock?

Why carbon steel? Because carbon steel will absorb some of the shock and "bend" the crystal to rupture instead of shattering the whole piece. And because the carbon will serve as fuel for the rest of the reaction on its way to the pan. Because old time folks were clever well beyond their understanding of chemistry.

Why pieces of steel in the pan when empty? Because you are high-speed-jabbing crystal-rock into it.

 

[Sidney Smith]

Im of the opinion that its a combination of three things that set off the charge

Sparks ignite the powder, flames result from the burning powder, and radiant heat from the flames are all part of the process.

 

[GregLaRoche]

You could be right.

 

[Danny Ross]

Omhra I am trying to figure out if we are saying the same thing or something different.


A sharp piece of flint (or other mineral with the hardness of 7 or greater) being held in the jaws of the cock, then falling forward under the pressure of the spring, scraping the frizzen creating sparks, is no different than using a steel striker and a piece of flint with char cloth or punk wood to create embers. The flint needs to be sharp to scrape the minute pieces metal off the harden face of the steel. "The pyrophoricity of the carbon steel results in the metal shavings oxidizing in the air becoming molten." from Wikipedia. As I understand it the face being struck needs to be harden, but softer than the stone, so only those minute shavings of steel are scraped off (friction) creating the sparks which are molten pieces of the metal. I am guessing, but the higher the carbon content of the metal being used increases the volatility of the metal when scraped producing more and hotter sparks. The less carbon fewer sparks are created. The softer the metal the flint gouges the metal instead of shaving/scraping the metal. DANNY

 

[GregLaRoche]

The question I am asking is not about the flint and frizzen, but what happens after the spark ignites the priming powder. What is the chain of events that ignite the powder in the chamber. Sparks, fuse effect, flame or maybe radiant heat. So far there have been a lot of theories proposed, but not one that that I can see is proven.

 

[M. De Land]

The question I am asking is not about the flint and frizzen, but what happens after the spark ignites the priming powder. What is the chain of events that ignite the powder in the chamber. Sparks, fuse effect, flame or maybe radiant heat. So far there have been a lot of theories proposed, but not one that that I can see is proven.

Perhaps the way to approach this is from the least efficient way to ignite BP to the the most efficient method that is present in a flint lock. The main charge can be instigated by conduction or radiation (sparks or flash) the later is the fastest and most efficient method of heat transfer from that produced from a flint lock. So technically it would be radiant energy that is being transferred from the pan powder flash.
BP cannot be ignited by pressure alone as I have tested this several times on and anvil with a hammer.

 

[Zonie]

When I think of "radiant energy" I think of a fixed source of heat such as a fire, radiating light waves thru the surrounding air and heating up whatever is being struck by these light waves. The word "radiant" indicates that it is radiation from the fire that does the heating. The actual fire never makes contact with the heated object.

With the flash of priming powder in the pan on the other hand, it is the actual flame front from the burning powder that expands hitting the barrel and in doing so, it passes thru the vent hole. The actual flame from the prime, reaches the powder in the barrel and ignites the main powder charge almost instantly. This can be seen in Pletch's high speed films that are looking down the barrel when the pan powder ignites.

This is the reason having the main powder charge as close to the source of the fire as possible greatly improves the speed that the flintlock fires. It is also the reason very small vent holes greatly reduce the reliability of a flintlock.

It's pretty easy to envision why the burning flame speeds the ignition of the powder. Just imagine holding your hand 1 inch from a flame. It is receiving "radiant energy" from the flame. Yes, the hand will get very warm, very quickly but little damage will happen if you move your hand away after a few seconds.
Now, imagine sticking your hand into the flames. Instant burning of the flesh will be the result with no time to move your hand away.

 

[ApprenticeBuilder]

With the flash of priming powder in the pan on the other hand, it is the actual flame front from the burning powder that expands hitting the barrel and in doing so, it passes thru the vent hole. The actual flame from the prime, reaches the powder in the barrel and ignites the main powder charge almost instantly. This can be seen in Pletch's high speed films that are looking down the barrel when the pan powder ignites.

^^^^^^^^^^^^^^This right here^^^^^^^^^^^^^^

This information is available, just need to do the due diligence and read the material, doesn't matter what you think you heard or saw, the tests prove that some of the long ingrained beliefs are just not correct.

 

[BV]

The question I am asking is not about the flint and frizzen, but what happens after the spark ignites the priming powder. What is the chain of events that ignite the powder in the chamber. Sparks, fuse effect, flame or maybe radiant heat. So far there have been a lot of theories proposed, but not one that that I can see is proven.

I doubt you are going to see anything proven. My advice is just be happy the gun went off, unless you have so few problems in life that you have to go looking for them. I chalk it up to voodoo myself, and I live the most carefree existance of anyone I know.

 

[GregLaRoche]

Finding out more about things is part of the hobby for me. The knowledge may even enable me to shoot a bit better.

 

[BV]

It's just going to give you a headache.

 

[GregLaRoche]

Only if I let it.

 

[BV]

I'm in your corner. I'm just afraid you'll twist your mind over this and start drooling in your pan. It'll never go off then.

 

[smo]

No spark, No fire..... in a flintlock gun under normal shooting conditions.

Flint hits the frizzen steel, creates a spark. Spark fires priming powder, the flash/heat/flame front / from priming powder ignites the main charge... Nothings changed.

I’ve still got an image of someone with a burning glass trying to focus the little heat source into the pan while staying on target...

 

[Dude]

Ok - I've got a question. The point was made earlier that with an empty pan, 1 out of 10 times, the main charge would go off. That tells me sparks managed to reach the main charge, rather than some left over powder flaring up. Is that wrong thinking?

If that's the case, why not just funnel the sparks straight into the main charge? Seems that would be a simpler and more direct ignition solution. If that was correct, I'm sure that's the way it would have been done. So what's the problem or reason it wasn't done that way? Why have sparks ignite some powder that then produces a flame front passing through a small port to ignite the main charge, rather than funnel the sparks straight to the chamber?

 

[Grenadier1758]

In my case when fired my smoothbore without any powder in the pan, I had carefully knapped the flint while the gun was loaded by first plugging the touch hole with my feather then using my brass knapping tool to flake off the edge to get the edge sharp. I removed the feather when I closed the frizzen, pointed the muzzle down range, notified the nearby range officer that I was going to see if I had spark after knapping the flint and with the gun at my waist to see if I had spark, pulled the trigger. In that slow down, I recall that I must have pulled out a couple of grains of powder from the touch hole liner. A spark lazily wandered over next to that powder grain. I don't remember seeing any sparks enter the touch hole. There was an orange glow starting to grow from that grain and perhaps a couple of other grains nearby all happening near the touch hole. Then there was the jet of flame from the touch hole and the gun fired. There was just enough heat generated by those few grains of powder to ignite the powder that had been in the cavity in the touch hole liner.

Since then I had several occasions where I had my loaded gun, lots of sparks and a failure to fire. There's no way to guarantee that the sparks from the frizzen would get directed into the touch hole for ignition.