poured in more of his 3F Pyrodex into the drum
That could be a clue. The more could indicate there is a blockage in the flash channel not allowing his propellant to fill the drum. Worth check out.
poured in more of his 3F Pyrodex into the drum
Rifleman1776 said:He is wrong about bp. And many genuine experts before him have written on the subject. Test it yourself. Put some bp in an open container and leave setting in your bathroom for a period of time. (the most humid room in a house) It will not get funky or clumpy.
colorado clyde said:Ok ! I got tired of arguing, so I called Hodgon powder co. and talked to one of their technicians (very nice fellow).
Hodgon is the maker of Pyrodex and Goex.
I asked him if Pyrodex and Black powder were hygrosopic.
He said “YES! All pyrotechnic powders are hygroscopic, BP or substitute it doesn’t matter there is no such thing as a non-hygroscopic pyrotechnic compound.”
Straight from the horses mouth.
:v
Does this help?
Some state that it is very Hygroscopic and this I do not agree
So while soaking BP in water as done during the manufacturing process makes it wet, leaving it exposed to even high humidity affects it very little and that is why many will say it's not hygroscopic, which in the case of BP has to do with it's absorption of moisture due to humidity and not full exposure to water as in soaking it when falling in a creek, etc. which I have had happen and it dried out just fine with no breakdown of quality."When high-purity potassium nitrate is used to fabricate the black powder the glaze imparts a degree of moisture resistance to the powder grains. Below 90% relative humidity the powder will be little affected by water vapor in the air. Above 90% R.H. the powder grains will pick up only trace amounts of moisture which will be quickly passed back to the air when the R.H. falls below 90%." The glaze on black powder grains is not graphite but a thin shell of potassium nitrate produced "by tumbling the grains during drying the crystals of potassium nitrate are compacted and fused into a thin shell, or skin, covering the surfaces of the powder grains. Under high magnification this thin skin, or shell, will give the appearance that the powder has been coated with glass."
The need to take a close look at the hygroscopic behavior of black powder bore fouling, or residue, became evident in the Fall of 1999 and both the Spring and Fall of the year 2000. On certain days of shooting the bore fouling would be seen as a thick coating of dry powdery fouling in the bore while the next day the bore fouling might be moist and paste?like with the same can of powder being used in the gun. With the dry powdery bore fouling it was nearly impossible to reload the rifle without running a wet cleaning patch down the bore. Damp patches would do little more than pack the dry powder into a hard cake in the bore. Only very wet patches would give a clean bore. A brand of patch lube that previously had worked flawlessly in reloading without having to wipe the bore suddenly seemed not to work at all.
From late Sept. 200 through mid?Dec. 2001 shooting days were selected by weather conditions to give a range of temperature and relative humidity to observe how the weather influenced the bore fouling in the rifle.
By watching the consistency, or "texture" of the bore fouling and both the air temperature and the relative humidity a pattern began to evolve.
If the relative humidity was 30%, or lower, the powder residue in the bore would be dry and powdery. Pressure applied by a damp cleaning patch, or by a patched round ball in reloading without wiping, the bore fouling would be compacted into a hard cake that adhered strongly to the bore surfaces. If the relative humidity was above 40% the bore fouling would be moist. The degree of moistness increasing with increases in the relative humidity.
In this work it became clear that the black powder fouling exhibited this hygroscopic property in varying degrees. The shooting results were compared to both the temperature and the relative humidity in regards to the amount of water present in the air in terms of grains of water per cubic foot of air. There is a great difference in the amount of water in the air when one compares 30% R.H. at 30 degrees F verus 30% R.H. at 70 degrees F. But the results showed that the hygroscopic behavior did not reflect changes in the actual amount of water in the air at a given level of relative humidity at a given temperature. The only relationship that could be seen was the percent relative humidity. That appeared to be the only factor involved.
So then it was back to the works of Noble & Abel to look at what chemical compounds are present in black powder bore fouling. Work on the pH of black powder residue showed the presence of potassium carbonate, or potash. The gunpowder residue analysis work of Noble & Abel shows that the major portions of the solid residue consists of potassium carbonate and potassium sulfate. The exact proportions of these in the residue will change somewhat with the brand of powder being used and the temperature at which the powder burns. But in any case there is a greater amount of potassium carbonate compared to potassium sulfate. Roughly 3 to 4 times as much potassium carbonate as potassium sulfate.
To then view how potassium carbonate governs the hygroscopic behavior of black powder residue a shallow dish containing pure potassium carbonate was placed outside under a roofed over deck. As the relative humidity changed with changes in the weather the potassium carbonate was observed. It was found that when the relative humidity was 30% or below the potassium carbonate would be a dry white powder. As the relative humidity rose above 30% the potassium carbonate would become damp. At 40 to 60% relative humidity the potassium carbonate would form a paste?like mass. At 80% relative humidity the potassium carbonate began to liquify.
What this showed was that at 30% R.H., or less, the potassium carbonate was for all practical purposes non-hygroscopic. From 30% R.h. to 60% R.H. the potassium carbonate could be classed as being hygroscopic. Above 60% R.H. the potassium carbonate would be classed as being deliquescent in nature.
According to the work of Noble & Abel, unless a black powder is specifically formulated and processed to be a "moist-burning" powder it will produce no water as a product of combustion.
This information was tested by flashing 500 grains of two different brands of black powder, in 10 grain increments, in metal salve tins. These were capped and weighed as soon as the last increment had been flashed . These were then placed in an oven at 150 degrees F for an hour to check for any weight loss. Then an additional hour at 250 degrees F. No weight loss that would be indicative of any moisture loss was observed.
In putting all of this together. Except for the Swiss made black powder, none of the black powders currently on the market produce water as a product of powder combustion. They will therefor produce a dry fouling in the bore. Any moistening of the bore fouling comes about when the spent powder gases leave the bore after the projectile leaves the muzzle. This results in a rapid inrush of atmospheric air into the bore. This "fresh air" then becomes a source of water for any moistening of the bore fouling. With the potassium carbonate portion of the bore fouling determining how much water could be pulled from this air.
An Important Aside.
The work on the hygroscopic nature of black powder fouling raised other issues in this work. Most importantly, after rusting in the bore of the gun. One will see claims for patch and bullet lubes that eliminate bore fouling, eliminate rust and corrosion and black powder substitutes that are non-corrosive.
NEVER take such claims as 100% factual.
In the work on the hygroscopic properties of black powder bore fouling we see the fouling as being non-hygroscopic at 30%, or less, relative humidity. That also means that the bore fouling will be almost non-corrosive at a relative humidity level of 30% or less. If the bore fouling does not pick up moisture there can be no rust. The rusting or pit corrosion in the bore is an electrolytic corrosion which requires the presence of a minimum amount of water present in the bore fouling. So while a gun might be left with a fouled bore one time with no signs of rusting the same might not be true on another day where the humidity is high enough to cause the fouling to pick up moisture.
One will see a claim that when a black powder substitute does not contain sulfur there will be no sulfur corrosion. In actuality, sulfur is not the corrosive agent in black powder. Gun bore "corrosion" may be promoted by two chemical compounds. If the potassium nitrate used in the powder, black powder or any of its substitutes, you may see chloride pit corrosion in the bore if the potassium nitrate contained any residual potassium chloride. Potassium carbonate, in itself, will cause the formation of thin surface films of rust on unprotected ferrous metals. As long as the propellant powder uses potassium nitrate in the formulation it will produce potassium carbonate as a product of combustion. So when it comes to hygroscopic properties and the possibility of after rusting the various black powder substitutes should be treated as one would treat the use of black powder in a gun. They all have the ability to damage a bore under the right conditions. Never leave the bore fouled for any length of time and always watch for signs of rusting on cleaning patches when setting the gun up to shoot after a period of storage. Rust is not always red. When mixed with a patch lube the rust may well show up as a brown stain on the cleaning patch used to prepared the bore for shooting.
colorado clyde said:Thank you for validating the major points of my argument, especially confirming that BP is hygroscopic.
quote]
Sorry but you read it wrong - as Bill Knight noted BP itself is NOT hygroscopic but BP residue is when the humidity is above 30%, so no I the info/facts I posted does not support you're argument.
hy.gro.scop.ic Pronunciation: "hI-gr&-'skä-pik
Function: adjective Etymology: hygroscope,
an instrument showing changes in humidity + [^1]-ic;
from the use of such materials in the hygroscope Date: 1790
1 : readily taking up and retaining moisture
2 : taken up and retained under some conditions of humidity and temperature
- hy.gro.scop.ic.i.ty /-(")sk@-'pi-s&-tE/ noun
Being hygroscopic in the case of BP is not just the ability to absorb water as is done during manufacturing, but rather whether the finished item absorbs water from the atmosphere i.e High relative humidity + temperature.
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