Is excess powder really blown out?

[Black Hand]

SHOOT IT IN THE DARK
YOU WILL FIND OUT

How will this tell you anything?

 

[Zonie]

Anyone who has seen a muzzleloader shooting black powder in the dark can't help but notice there isn't a little flash like a modern gun makes.
There is a HUGE ball of fire caused by the still burning powder outside the barrel.

I'm not saying that all of the powder that didn't burn while it was still in the barrel is burned in that flash but I do know, black powder will ignite easily if any of that fireball contacts it.

If that does happen, I think that most of the black stuff found on a white sheet after shooting over it would be burnt powder fouling.

 

[Carbon 6]

I love when the opinions are in full bloom. It's so pretty.

This reminds me of my wood stove, I've had some really hot fires in it, The kind where fire comes out the chimney, But I've never seen a block of firewood come flying out. Just burning gas and superheated ash.

 

[Britsmoothy]

IMO: Excessive powder burns outside the barrel. Have someone fire the gun at night. If the muzzle flare is longer than 18-24 inches the charge is excessive.

So 17" is ok then?

 

[smo]

So 17" is ok then?

Only in a 28" barrel or less! lol

 

[Idaholewis]

I bet there will still be residue and it's simply a by product of Goex's manufacturing processes.

Very plausible Waar, I don’t remember trying to pick the particles up to examine them? I remember it was blown out quite a ways (like 20 yards or better) from the Muzzle, and there was quite a bit of it. I wouldn’t think Fine ash would get that far out? Swiss powder on the other hand left NOTHING on the fresh snow.

This

I'm glad someone else knows the works and words of Bill Knight.

(remember 15yrs or so ago when there was the Goex quality issues?)
But he stated that it was not actually "un-burnt",, just large pieces of left over carbon from compromised powders on the market

This makes Sense, Dad has several Old Cans Of Goex, What we were seeing very well could have been large pieces of left over Carbon? It looked exactly like it did when it was loaded, They were large pieces, heavy enough to travel a good 20 yards or Better, i just assumed it to be unburned Powder? When i stand back and watch Someone shoot Goex i see Sparks, and Embers Tumbling out, Little Smoking Embers that Fly 10 feet or more. Swiss Blackpowder Does NOT do that? Swiss left NOTHING Behind on the Snow, Even 80 Grains in a 10” Barreled Pistol.

 

[Britsmoothy]

Only in a 28" barrel or less! lol

 

[Juice Jaws]

IMO: Excessive powder burns outside the barrel. Have someone fire the gun at night. If the muzzle flare is longer than 18-24 inches the charge is excessive.

I am going to try this and see if I can get the wife to hold the measuring tape.

 

[George]

There's no argument that particles are blown out of the barrel, and the touchhole of a flinter. Since black powder burns at about 2140C/3800F, it would be very surprising if some of the solids...56% of the charge... left after BP burns weren't glowing hot or actually burning after they were blown out. That's easily seen in night photographs of firing, as in these.

Notice that in the photo of the rifle there are burning/glowing particles blown out from the pan. The rifle wasn't loaded, only the prime was fired. The normal priming charge in that gun is only about 1.75 grains of 4F, and yet a small explosion has obviously taken place. I don't have any idea what people mean when they say "excessive" powder is blown out. In excess of what? The accuracy charge? The maximum safe charge? More than the Davenport formula allows, maximum 'efficient' charge? Whichever, I doubt that the priming charge in that photo qualifies, but it's still blowing stuff out.

Since the ignition temperature of BP is apparently somewhere between 600F and 900F, how would even a little of it avoid being ignited at 3800F?

Spence

 

[Black Hand]

Spence,
A reasoned and logical answer, which will be ignored....

 

[J. Paul]

Muzzle Blasts magazine had an article several years ago after a statement was made that a muzzle loader couldnt be overcharged because there was a point at which unburned powder was pushed out and burned in front of the muzzle. Resulting article showed for every increase in powder charge there was an increase in pressure and velocity. They continued with the rifle test barrel until the pressures being reached were considered unsafe to further testing. The last several charges increased pressure only with no increase in velocity.

 

[Carbon 6]

Spence, those sparks are easily explained.

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

 

[George]

Spence, those sparks are easily explained.

Never was aware of that. Just a thought, it's not those sparks which we are interested in, actually. They are obviously burning or already burnt and glowing, whatever they are. If there is any unburned powder being blown out, it wouldn't be visible, even in the photos.

Spence

 

[Black Hand]

Spence, those sparks are easily explained.

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

The Potassium nitrate used in the making of powder is an oxidizer and it wouldn't be a stretch that it becomes superheated while donating oxygen to the reaction.

 

[George]

The last several charges increased pressure only with no increase in velocity.

Since velocity is directly proportional to the pressure, how is that possible?

An historical digression, fair warning to those not interested...
In early 18th century, Benjamin Robins was trying to figure out why barrels burst if the ball was not well seated on the powder. He had the idea that in some way the pressure was being increased, but he had no way to measure pressure. He knew that pressure and velocity were directly and inseparably linked, though, so he used a very thick-walled, rupture-proof barrel to fire some shots with powder and ball separated. He then used his newly invented pendulum, the first 'chronograph', to measure the velocity of those shots and found that they were consistently higher than normal with those charges. Using those increased velocities he calculated the pressure, validating his idea that they were increased.

Spence

 

[Col. Batguano]

Intuitively, there WILL be a point where more powder will produce decreasing velocities, but it's nowhere near where we would normally load a gun.

Taking this theory to the absurd, hypothetically, if you completely filled your barrel with powder, and just barely squeezed a ball under the muzzle to seat it, yes, your velocity would be less than if you did a more sensible, and less "Darwin Award seeking" sort of a load. Where is that number where ultimate velocity starts decreasing? My guess is somewhere around between 1/8 and 1/4 of the total volume of the barrel, but that's nothing more than a wild guess. Obviously you would need a pretty stout barrel to conduct this test, because pressures would really be up there. I'm certainly not going to try it.

 

[Carbon 6]

Since velocity is directly proportional to the pressure, how is that possible?

An historical digression, fair warning to those not interested...
In early 18th century, Benjamin Robins was trying to figure out why barrels burst if the ball was not well seated on the powder. He had the idea that in some way the pressure was being increased, but he had no way to measure pressure. He knew that pressure and velocity were directly and inseparably linked, though, so he used a very thick-walled, rupture-proof barrel to fire some shots with powder and ball separated. He then used his newly invented pendulum, the first 'chronograph', to measure the velocity of those shots and found that they were consistently higher than normal with those charges. Using those increased velocities he calculated the pressure, validating his idea that they were increased.

Spence

We need to discuss whether or not velocity and pressure are directly proportional as a separate topic however,
Robins was correct because loose powder burns faster and thus develops more pressure in a given space/time than tightly packed powder.
Also attributed to Blackwood and Bowden.

 

[Carbon 6]

When examining pressure, we need to understand a few basics about BP.
When BP burns it produces two types of gasses, flammable and non-flammable.
Pressure is increased by both production and by heating of those gasses. Temperature is proportional to volume in a gas, and as Spence told us "black powder burns at about 2140C/3800F"

 

[Black Hand]

When examining pressure, we need to understand a few basics about BP.
When BP burns it produces two types of gasses, flammable and non-flammable.
Pressure is increased by both production and by heating of those gasses. Temperature is proportional to volume in a gas, and as Spence told us "black powder burns at about 2140C/3800F"

PV=nRT
https://en.wikipedia.org/wiki/Ideal_gas_law

 

[Stumpkiller]

How about if you put your muzzleloader muzzle up against an empty but sealed cardboard box and fired it. Most of the ejects would be captured in the box.

Then take what is in the box, place it on a sheet of paper, and see if it "catches" when a match is applied.

Seems to me I recall a member doing this experiment some years back and writing about it here and there was some unburnt powder in with the rest of the ash.