Is excess powder really blown out?

[zimmerstutzen]

I don't agree.
The "fuse"affect is actually a Fuse like affect. A poor analogy.
A properly set up flintlock will not produce a "fuse like affect" Therefore the problem that causes it is not powder related unless the powder is fouled resulting in a hang type misfire.

Also you mentioned,



I guess I would add that that "hot gas" is actually on fire and close to 3000 degrees.

1. if that hot gas/fire/magma theory was correct, that the hot gas/fire/magma seeps all the way through the charge, the patch would burn through and the lead would melt.

2. A person with a "properly set up flintlock" does not get the click shhhhhhhhh boom because they have learned not to fill the pan with powder. Something newbies and greenhorns do, especially with touch holes on production guns that are lower than the top of the pan.

 

[Artificer]

The other thought mentioned was that all that hot gas seeps through the powder granules and lights them up. at what point does the gas from the rear of the charge push the unburned powder together like a wad ahead of the gas and only burn from the rear as it travels down bore.

That is a great question. At the beginning of the "deflagration" or burning of the powder, and especially when the powder column is ignited from the rear end, some of the unburned powder probably is pushed forward by the propellant gas, until it burns completely. I don't know for sure exactly how long of time that increases the burn time, but it has to be less than a couple thousandths of a second or maybe less than a thousandth of a second.

BP does not burn "instantaneously" inside a gun, but it burns very much faster than outside a gun, because it is in a partial container and the heat and pressure of the propellant gas acts on it.

Gus

 

[George]

BP does not burn "instantaneously" inside a gun, but it burns very much faster than outside a gun, because it is in a partial container and the heat and pressure of the propellant gas acts on it.

I don't think that's correct. I believe BP flashes in the open at the same speed as when contained, for all practical purposes.

In the old literature they use two term in discussing the burning of BP, enflamed and consumed. Enflamed means the outer surface of the granules has been set afire by the fast-moving heat wave. Consumed means the granule has been burned through to the center. The first happens very much faster than the second. The say the whole, combined process doesn't happen instantaneously, but is so quick it appears to be nearly so.

In reading their description, it occurs to me that those fiery streaks we see when we fire a gun at night are one of two things, either grains of powder which have been enflamed but not consumed and are still burning, or the glowing embers of grains already burned. Remember, BP burns at 3880F.

Spence

 

[Artificer]

I don't think that's correct. I believe BP flashes in the open at the same speed as when contained, for all practical purposes.

Spence

OK, perhaps I should have written that BP burns faster in the flintlock barrel because there is a flash/jet of flame that sets it off compared to a spark or sparks setting it off in the pan.

BP also burns faster in a barrel than it does in a straw or fuze, even though a flame imay be used to set it off.

Gus

 

[George]

Cleator has an extended discussion of this question, and basically accepts the ideas of Robins, but explains that other people don't agree. He describes contrary evidence presented by others, concludes that he can't decide between the two camps. And we still can't.

Spence

 

[Carbon 6]

In reading their description, it occurs to me that those fiery streaks we see when we fire a gun at night are one of two things, either grains of powder which have been enflamed but not consumed and are still burning, or the glowing embers of grains already burned. Remember, BP burns at 3880F.

Spence

Spence, those sparks are easily explained.

According to Blackwood and Bowden those "sparks" you see are actually molten droplets of potassium salts.

Here is some grist for the mill,
If you look closely some of the sparks emanating from the pan some seem to be deflagrating as they move through the air, evident by the smoke trails. Others are not supporting the molten potassium theory.
Everything coming out the muzzle and appears to be fully burnt.
To me this suggests that it could be possible (but unlikely) for a few grains of unburnt powder to be thrown clear of an explosion in the open, but not when contained.

 

[smo]

I think that what Spence said is correct as too the flashing of black powder.

Inside the barrel its under pressure more so than in the pan,
But I would think the detonation rate would be the same....QUICK!

 

[Carbon 6]

Inside the barrel its under pressure more so than in the pan,
But I would think the detonation rate would be the same....QUICK!

BP doesn't detonate.

 

[dlidster]

This thread came to mind yesterday while a was chronographing over freshly-fallen snow. After a string of five shots of 50 gr of T7 fffg and .490 PRBs there wasn't a trace of any black ejecta in the snow. Would this indicate that the discussion going on here is related to real black powder only?

Here's why I ask. Curious about whether the T7 and Black MZ truly are as clean-burning as they've always appeared to me, I ran a simple test today. I ignited a 25 gr pile each of T7 ffg, T7 fffg, and Black MZ on a metal jar lid. After each "whoosh" I brushed what little was left onto a clean paper towel. The T7s left just a trace and the Black MZ almost nothing. I'd be happy to repeat the experiment and photograph the results, but trust me, almost nothing was left.

As an aside, in my .50 cal. T/C Hawken 50 gr of T7 fffg delivered a five-shot average of 1657 fps. 80 gr of T7 ffg delivers 1663 fps. And 100 gr of Black MZ delivers 1596 fps. FWIW, 70 gr of T7 ffg at 1577 fps gives me my best accuracy.

 

[Carbon 6]

Would this indicate that the discussion going on here is related to real black powder only?.

Yes! Because Tipple seven and Black MZ are completely different powders than black powder. We are not comparing powders. those other powders are classified and burn differently.

 

[Artificer]

On the deflagration or "burning" rate of BP outside a barrel and inside.

http://www.ctmuzzleloaders.com/ctml_experiments/bp_burning/bp_burning.html

Gus

 

[Carbon 6]

On the deflagration or "burning" rate of BP outside a barrel and inside.

http://www.ctmuzzleloaders.com/ctml_experiments/bp_burning/bp_burning.html

Gus

 

[smo]

BP doesn't detonate.

My Bad, I should have said “burn”.

I always thought once it was compressed , then it would detonate vs burn.... otherwise it would only fizzle / flash...

I’m not a rocket scientist just an old boy that knows when BP is compressed you get a BANG! Vs a Whooooosh!

But I would think the “burn rate” once an ignition source is supplied would be the same for compressed black powder vs loose black powder.

 

[Black Hand]

But I would think the “burn rate” once an ignition source is supplied would be the same for compressed black powder vs loose black powder.

If that were the case, they would not need to put the hole up the center of the BP pellets sold for modern muzzleloaders. At least,that is my thought on the matter.

 

[Carbon 6]

If that were the case, they would not need to put the hole up the center of the BP pellets sold for modern muzzleloaders. At least,that is my thought on the matter.

Who makes black powder pellets?

 

[Black Hand]

Who makes black powder pellets?

Good catch. I was thinking of the Pyrodex pellets and not the propellant used to make them. But I suspect the situation would be similar - as it takes time for the ignition to propagate from its initiation point through the granules.

 

[smo]

Great info Gus.

Who wrote the article?

 

[Carbon 6]

I’m not a rocket scientist just an old boy that knows when BP is compressed you get a BANG! Vs a Whooooosh!
.

I think you mean to say "contained" versus "compressed".
Actually the more BP is compressed the slower it deflagrates, essentially you end up making one large granule.

Bp burns the fastest when loose, When contained, the heat and pressure accelerate rate of decomposition When heavily compressed the rated is slowed.

I do not know for sure what the results are for being both compressed and contained.

A person could easily determine this practically with a chronograph.

 

[Carbon 6]

But I suspect the situation would be similar - as it takes time for the ignition to propagate from its initiation point through the granules.

I assume that because they are compressed, the hole is there to speed up the burning rate. Otherwise they might act more like model rocket engines, than BP.

 

[smo]

I don’t own a crony, as long as my ball will stay on target and penetration on the animal is good that’s really all that conserns me anymore.