My homemade black powder

[almar]

Well if you know the weight of the powder you put in the die, and how high the fill mark is with a lightly hand pressed powder , then you can get the initial density. With a target density and the same weight you then know how much you need to reduce the volume..you just measure the powder weight everytime and repeat to the same mark. The great part is no more waiting for an hour each time, a minute or so is all it took. This seems to be more in line with the litterature in waltham abbey. Some moisture is important i beleive to ensure a good enough hardness of the grains and compressability.

[DoubleBuck]

Very ingenious, Almar!
So you're saying it will hold that density after only a minute? Why were we having so much trouble getting to that factory density? The first time I ever achieved it, was with a 20 ton jack and cycling it a couple of times, for an hour. My 60 grain volume measure was spot on with Swiss, and has always been higher volume, by weight with my H.M., until that first higher density batch. I must be missing something.

[almar]

I don't know Doublebuck. The book says its optimal between 1.6 and 1.7. Which is why I wanted 1.64. I got as high as 2 g/cc with my pucks and got higher than swiss density when I pushed my press and kept it for an hour. After reading that books chapter on density it makes so much sense to keep the density lower and not care about the weight per volume measure of the final product per say and try to match it to commercial stuff. Higher density leads to slower powder and more fouling. from what I measured, if you cant get it past 1.85 or so with 10 tons (way too high a density), then I don't know why, maybe not enough moisture? not fine enough? Hard to say from so far away. I'm thinking that the optimal is to get it as fine as physically possible but not push the density to higher levels than required.

A higher density and harder grains are better for transporting the powder but make sure you have a look at the last paragraph of that chapter if you would, it puts things in perspective.

This is constantly evolving....

[Vettepilot]

Hmmm...

Seems like we're missing something here. My understanding is the factories use around 3500 pounds per square inch, and that's what it takes to get the sulphur to plasticize. You figure the square inch area of your die, multiply by 3500, and that "should" have you there. The only variables in this might be moisture content, and how long you hold it, but you're looking for a final product that has a density of 1.7 g/cc. It's not a proportion of compression, it's the density of the final result.

So... 1.7 g/cc should mean just that. If you have 1 cc of powder, it should weigh 1.7 grams. It shouldn't matter how much it weighed when you started, as long as it weighs 1.7 g/cc when you're done.

Or am I missing something??

Vettepilot

[ChrisPer]

I calculate density not on powder but on pucks. About 1.77, 1.8 is what I expect.

Then there is the bulk density of the powder which includes the pore space. I use a 100gn volume measure and weigh the result. I am getting about 89gn, and Swiss gets about 102gn.
I dont know how to do better; I think that I am using too narrow a range on my sieves, which increases pore size. ANd sharper corners I would have thought result in bigger pores. But when I tumbled it to reduce the sharpness of the grains I didn't measure any change in the bulk density.

[Vettepilot]

Regarding your question on your grain size, you might try checking Swiss powder, on your grading screens.

And yeah; everything I've ever read had the volume of the (commercial) powder in grains, right at 1:1 give or take a little, with the weight in grains. That is, a 100 grain volume of commercial powder weighs ~100 +/-.

Vettepilot

[almar]

I just measured Swiss 3f in a 4cc lee scoop and it gave about 4g so 1g/cc. To get 1.7 you would need insanely dense pucks closer to 3.4g/cc aprox (insanity).

[almar]

Im going to choose to not bother at all with density of the powder or use commercial powder as a bench mark at All for density. I dont see why i would, maybe they have their reasons to make it denser? I initially thought it would make a better powder but now i dont think so. So, i will monitor is the density of the puck for now and try to keep it at around 1.7.

[Vettepilot]

I just measured Swiss 3f in a 4cc lee scoop and it gave about 4g so 1g/cc. To get 1.7 you would need insanely dense pucks closer to 3.4g/cc aprox (insanity).

Well, surely the oft quoted 1.7 g/cc is black powder as a mass; not as a granulated powder. The granulated powder is full of air spaces!

I would think the only judge of granulated powder density, would be as ChrisPer said; the ~100 +/- grain weight per 100 grain volume measure.

We you were stating the densities of your powders previously, how exactly were you measuring/calculating them?

Vettepilot

[Vettepilot]

Here's some more interesting info from some others whom are pondering densities:

https://www.muzzleloadingforum.com/t...density.44034/

Vettepilot

[DoubleBuck]

I think we're all pretty much saying the same thing and the confusion is coming from the way we're saying it.
We all agree that dry PUCK density needs to be around 1.7 grams per CC. That seems to be the Commercial target and ours, as well.
The powder once broken up has grain density the same as it was in the puck. The size and shape of those grains is what determines the volume/weight density in a measure.
If Swiss 2FF gives a weight of about 100 grains, in a 100 grain volume measure, and our H.M. is less, but our pucks DRY both had the 1.7 g/cc density, then the only difference should be the size and shape of the grains, in the measure. Same with our powder. If those grains of powder are different in size and shape, but equal density, the larger grain sizes with smooth edges will weigh more in a volume measure, than smaller grains with rough edges. You can simply get more weight in the same space.
If we can get the 1.7 density goal and not the 100 grain weight in a 100 grain volume measure, I would submit that our grain sizes and/or shape are not equal, to a powder that will.
My personal powder has always weighed light, in a volume measure, to Swiss, until about a year ago, when someone came up with the cycling the press and longer wait times, on compression. From that time, my powder became nearly equal to Swiss, in Volume, for a given weight. I haven't changed screens, or other processes. My last measured dry puck had a density of 1.722 g/cc. But using a 20 ton press, and letting it set an hour, I'm now wondering if I have had pucks much greater in density and didn't know it. Or why that puck set six hours in the press when I went to bed and forgot it, and yet it only had a density of 1.7. Nonetheless, I'm happy it did. BUT, I don't know if I wasn't getting the same density the old way of pressing (hit it with 20 tons for a minute and call it good), or not. SOMETHING changed when I started waiting longer on the press, and cycling it. I have checked densities before and got that same 1.7, but only when I started pressing longer and cycling, did it hit the volume mark in the measure.

[Vettepilot]

I think we're all pretty much saying the same thing and the confusion is coming from the way we're saying it.
We all agree that dry PUCK density needs to be around 1.7 grams per CC. That seems to be the Commercial target and ours, as well.
The powder once broken up has grain density the same as it was in the puck. The size and shape of those grains is what determines the volume/weight density in a measure.
If Swiss 2FF gives a weight of about 100 grains, in a 100 grain volume measure, and our H.M. is less, but our pucks DRY both had the 1.7 g/cc density, then the only difference should be the size and shape of the grains, in the measure. Same with our powder. If those grains of powder are different in size and shape, but equal density, the larger grain sizes with smooth edges will weigh more in a volume measure, than smaller grains with rough edges. You can simply get more weight in the same space.
If we can get the 1.7 density goal and not the 100 grain weight in a 100 grain volume measure, I would submit that our grain sizes and/or shape are not equal, to a powder that will.
My personal powder has always weighed light, in a volume measure, to Swiss, until about a year ago, when someone came up with the cycling the press and longer wait times, on compression. From that time, my powder became nearly equal to Swiss, in Volume, for a given weight. I haven't changed screens, or other processes. My last measured dry puck had a density of 1.722 g/cc. But using a 20 ton press, and letting it set an hour, I'm now wondering if I have had pucks much greater in density and didn't know it. Or why that puck set six hours in the press when I went to bed and forgot it, and yet it only had a density of 1.7. Nonetheless, I'm happy it did. BUT, I don't know if I wasn't getting the same density the old way of pressing (hit it with 20 tons for a minute and call it good), or not. SOMETHING changed when I started waiting longer on the press, and cycling it. I have checked densities before and got that same 1.7, but only when I started pressing longer and cycling, did it hit the volume mark in the measure.

Great post, and I agree entirely. This is it "in a nut shell" and in one post.

ALMAR: You're sounding a touch exasperated, and rightly so. But you're right there with all this. Just consolidate what you have and what you know. If I were you, I don't believe I would go searching for more; just consolidate/finalize, and put in motion all you have accomplished; the great work you've done.

Here's enough to make your brain hurt though, if any of you want more "punishment."

Vettepilot

[DoubleBuck]

VettePilot;
That was a good read, you posted!

[almar]

Well, surely the oft quoted 1.7 g/cc is black powder as a mass; not as a granulated powder. The granulated powder is full of air spaces!

I would think the only judge of granulated powder density, would be as ChrisPer said; the ~100 +/- grain weight per 100 grain volume measure.

We you were stating the densities of your powders previously, how exactly were you measuring/calculating them?

Vettepilot

not sure what you mean? For 30 grains measured by volume in the powder measure i weighed the 30 grains on scale... For the pucks, weight/puck volume...
example
diameter 3.00 in
weight 63.40 gr
thickness 0.29 in
disk Area 7.07 sq.in
Volume 2.05 cubic in.
factor 16.39 cc per CI
CC 33.57 cc

density 1.89


Vette im stunned that you got that hahaha...maybe a little impatient plus I need a vacation real bad. Ill just go with what i have now, make another batch and polish it this time.

[almar]

I think we're all pretty much saying the same thing and the confusion is coming from the way we're saying it.
We all agree that dry PUCK density needs to be around 1.7 grams per CC. That seems to be the Commercial target and ours, as well.
The powder once broken up has grain density the same as it was in the puck. The size and shape of those grains is what determines the volume/weight density in a measure.
If Swiss 2FF gives a weight of about 100 grains, in a 100 grain volume measure, and our H.M. is less, but our pucks DRY both had the 1.7 g/cc density, then the only difference should be the size and shape of the grains, in the measure. Same with our powder. If those grains of powder are different in size and shape, but equal density, the larger grain sizes with smooth edges will weigh more in a volume measure, than smaller grains with rough edges. You can simply get more weight in the same space.
If we can get the 1.7 density goal and not the 100 grain weight in a 100 grain volume measure, I would submit that our grain sizes and/or shape are not equal, to a powder that will.
My personal powder has always weighed light, in a volume measure, to Swiss, until about a year ago, when someone came up with the cycling the press and longer wait times, on compression. From that time, my powder became nearly equal to Swiss, in Volume, for a given weight. I haven't changed screens, or other processes. My last measured dry puck had a density of 1.722 g/cc. But using a 20 ton press, and letting it set an hour, I'm now wondering if I have had pucks much greater in density and didn't know it. Or why that puck set six hours in the press when I went to bed and forgot it, and yet it only had a density of 1.7. Nonetheless, I'm happy it did. BUT, I don't know if I wasn't getting the same density the old way of pressing (hit it with 20 tons for a minute and call it good), or not. SOMETHING changed when I started waiting longer on the press, and cycling it. I have checked densities before and got that same 1.7, but only when I started pressing longer and cycling, did it hit the volume mark in the measure.

Thank you Double buck! good post! Maybe thats what it is...grain shape and size...

[Vettepilot]

not sure what you mean? For 30 grains measured by volume in the powder measure i weighed the 30 grains on scale... For the pucks, weight/puck volume...
example
diameter 3.00 in
weight 63.40 gr
thickness 0.29 in
disk Area 7.07 sq.in
Volume 2.05 cubic in.
factor 16.39 cc per CI
CC 33.57 cc

density 1.89


Vette im stunned that you got that hahaha...maybe a little impatient plus I need a vacation real bad. Ill just go with what i have now, make another batch and polish it this time.

Ha! Yeah, I'm pretty sensitive to others, and sometimes too much for myself.

When I get to the point you're at, I have to FORCE myself to walk away, and come back in a few days with a fresh head. It's dam hard for me to do, but when I succeed in taking a break, I'm always glad I did, and subseqently more productive. It's amazing what I come up with in my sleep, or right afterwards too!

I don't have time right now to check your math, but I'm sure it's fine. More importantly is your 30 grain weight for 30 grain volume. THAT'S what everybody has been struggling to reach, with dam few successes. But keep in mind, that's really only important for cartridge loading. For "front stuffers", if you have to weigh your charges, and/or increase your volumetric measure a few per cent, so what??

Vettepilot

[Vettepilot]

If you're only shooting front stuffers, my advice would be go back to a for sure 1.7 g/cc density, take whatever granular density that gives you, and go enjoy the more powerful, cleaner powder you created. JMHO

Vettepilot

[DoubleBuck]

I just got the notice my grinder will be here in the morning. It's just like the anticipated Christmas present!!!!
"Man, what's in this coffee, Kidder?"
"A dash of Potassium Nitrate, dripped through brown charcoal, with a hint of Sulfur, and a small skoash of pure soft lead." You like it? Good, ain't it?"

[almar]

Ha! Yeah, I'm pretty sensitive to others, and sometimes too much for myself.

When I get to the point you're at, I have to FORCE myself to walk away, and come back in a few days with a fresh head. It's dam hard for me to do, but when I succeed in taking a break, I'm always glad I did, and subseqently more productive. It's amazing what I come up with in my sleep, or right afterwards too!

I don't have time right now to check your math, but I'm sure it's fine. More importantly is your 30 grain weight for 30 grain volume. THAT'S what everybody has been struggling to reach, with dam few successes. But keep in mind, that's really only important for cartridge loading. For "front stuffers", if you have to weigh your charges, and/or increase your volumetric measure a few per cent, so what??

Vettepilot

Ive been able to get pucks very very dense with double bucks method, I think that's what got me to a the same weight per volume. So that caused me to develop the dogma that commercial guys have the same density, but like doublebuck said and I think indian joe mentioned awhile back, it could be how the grains fill the powder measure. I just screened the 1.64 g/cc pucks and they give me 23.5 grains per 30 volume....my pucks are flat and the side thicknesses may vary slightly by 10-15 thou so I take an average thickness. the difference between the max and min is not very big anyways.

Edit: 28.2 gr/30gr not 23.5, I forgot that my powder measure was on 25 gr I also did some more screening. to only gather the grains between 30 and 40 mesh. This isn't to far from the mark after all, if I push it up slightly from 1.64 density to 1.7 I might be there...then again, maybe this is where I want to be.

[almar]

I just got the notice my grinder will be here in the morning. It's just like the anticipated Christmas present!!!!
"Man, what's in this coffee, Kidder?"
"A dash of Potassium Nitrate, dripped through brown charcoal, with a hint of Sulfur, and a small skoash of pure soft lead." You like it? Good, ain't it?"

that would get you going in the morning.