Black Powder troubles thread

[TYRONEEZEKIEL]

Ive noticed that my BP after milling isn't well.. Black.. its a dull gray color, and it does not have that good thump like commercial stuff.. granted it is much finer than powdered sugar, and it blows the crud out of my old hand ground powder. I mill it for about 4-6 hours sometimes 8. I use standard 75:15:10 KNO3/charcoal/sulfur. and I use homemade pine or balsa charcoal.

 

Is this how it is supposed to be, since i know commercial is corned and compressed to 1.7 g/cc or should i mill it longer?

[Ventsi]

Are you testing the powder right out of the mill?

The dark color appears when using lighter c-coal.

Are you granulating it or pressing and corning?

The corned BP has a much better thump to it since if you take the same volume of corned vs. pulverone the corned BP actually has more BP since it has been compressed to a higher density , plus the jagged edges catch fire a lot better.

[TheSidewinder]

Tyrone, powder right out of the mill doesn't burn very well if it's just in a pile. Pressing and corning is one way to get good BP, but you can try "ricing" your BP. It's what I've done in the past.

 

Add 5% dextrin to your mix before milling, then mill it as you've usually done.

 

Wet the batch with JUST enough water to have it form a ball as you squeeze it and doesn't crumble if you drop it a foot, but not so much that it "bleeds" water when it's very tightly squeezed. (You'll have to experiment a little, that's part of pyro.)

 

Then form a tight ball of it and "grate" it through 20-30 mesh screen so it forms granules about as big as a half grain of rice. Let it dry thoroughly, outdoors but not in direct sunlight. Test a small amount and see if it hasn't improved.

[psyco_1322]

Black powder straight from the mill is not black. If your take black charcoal and add some white and yellow stuff, its not going to stay pure black, it gets diluted to a gray color. It also needs to be wetted and granulated for use in lifting things.

 

That powder should come out faster than commercial when you get it made right.

Edited May 4, 2009 by psyco_1322

[Mumbles]

The color is right. If you wet it and corn/granulate it, it gets the more familiar black color. When I take a small amount of mill powder, it burns in a very fast poof. It will often even make a smoke halo if the wind is low. If you try to test too much, it burns much slower. I use a pile about the size of a match head I suppose. A tip of my spatula. My powder sometimes comes out kind of granulated anyway from slight caking. If you have an optimized mill, 4 hours is all it really needs. If you have something less optimized, such as a rock tumbler, 8 hours would be a minimum, but longer is better.

[50AE]

The moisture plays an important role in black powder. Straight out the mill, the particles are just mixed, not integrated. The liquid (water or alcohol) will somehow "cement" the black powder, making the sulfur and the potassium nitrate stick tightly to the charcoal. That's why it becomes blacker, you can hardly see any nitrate. Edited May 4, 2009 by 50AE

[Arthur]

What you have is Greenmix, yes it is grey, yes it burns slowly. Pick a standard process for greenmix say 75 ;15 ;10 then add 3 - 5% dextrin and mill for say 8 hours in a small mill. Take the dry powder and damp it with a water/alcohol ( 75;25 ish) mix til it just holds together when squeezed by hand then grate the lump through a 10 - 20 mesh sieve or a fine cheese grater. Then dry the particles well. For shell use sieve the mixed particles, the coarser lumps are lift, the finer lumps are break and passes 100mesh is for making Black match or spoolettes, or is for returning to the mill next time.

[Swede]

Commercial BP like Goex is dense. They do it with giant roller mills; we do it with a ball mill + pressing to achieve the same thing. Further, I believe the color of commercial BP is as much from added graphite (to ensure free-flowing qualities) as it is from the BP itself.

[firetech]

Tyrone, I have a small rock tumbler type mill. I mill mine for 24 hrs. When wetted and grated through a window screen it makes an immpressive thump when its burned in a small pile ~1g. You might want to mill it for a bit longer.

[TYRONEEZEKIEL]

My mill has about a 4" ID by 11" jar which is directly driven by an ohio motors variable speed adjustable motor. I have about 200 .5" lead balls as my media, and i mill about 200g batches at a time. I am certain its not green mix.

[firetech]

Try either less comp at a time or longer milling time.

[Mumbles]

Firetech, do you have any idea what you're talking about? If not, you may want to refrain from posting. His jars are already underloaded with both composition and media. I have jars half the size, and it takes the same charge. At this load it takes 10-12 hours for good BP. Tyrone, I'd suspect you will need even longer than this. I'd venture a guess at around 18 hours.

[TYRONEEZEKIEL]

My media fills almost half of my jar, and put about 1/3 volume with Comp. How much more do you suggest?

[Mumbles]

Hmmmm, odd. I use about the same, it it fills my 6" long jar about half full too. That is roughly the correct load. 1/2 full of media, 1/4 full of composition. If my jar can handle 200g, you should be fine too.

 

Like I said in my pm, try a longer mill time and see if it helps. It will help determine if it is one of your materials, or if it's just the duration at fault.

 

Is your BP caking at all, or does it come out free flowing? If it's caking, it might be doing so before it can be adequately milled. Even though it's in there, it's not being acted upon for the full mill time.

[hondo]

so how do you keep your powder from caking in the mill. seems mine just started caking about 5 months ago and I tried adding cabosil which helped but I figure that will affect the speed of the power, but then I also press mine in my press to 3000 psi and hold for 15 minutes and then break up the pucks, I tried adding red gum and that seemed to slow the power down unlike some post I have read

 

so how do you stop the caking problem

[Mumbles]

I don't know, but if you figure it out, let me know. I think my KNO3 is a little bit damp. Mine is good by the time it's caked, so it doesn't affect my powder, but opening the jar halfway through and breaking apart the cake should help.

[TYRONEEZEKIEL]

My BP is certainly very clumpy when I open the jar. Screening it is sometimes difficult. I think it may have to do with the excessive humidity in texas. When I first milled my BP in the winter, it came out free flowing and very "squishy" ?

 

I have a jerky dehydrator that I use for drying pulverone. Could I dry my KNO3 right before i mill it to help with clumping?

[pyrogeorge]

i had the same problem..and i think that my charcoal was "wet" because of moisture.

pay attention how to store your charcoal,and take a look if your charcoal is wet.

[TYRONEEZEKIEL]

How will I know when my charcoal becomes wet?

[hondo]

I would be more inclined to think its the sulfur thats damp

charcoal is more water resistant, and I wouldnt think the potassium nitrate would be the issue either but after saying that I have noticed that the potassium nitrate I get now is in the form of crystals and not the fine powder it use to be and I think when it was in powder form it had cabosil to make it free flowing and non clumping so maybe the cabosil was keeping it from caking?, I did buy some cabosil just not sure of the amount to add and not affect the burn rate

 

anyones thoughts????

[hondo]

just go home, checked on my new BP batch and all cake up on the end of the ball mill, so I added 1.5 grams of cabosil to 150 grams of BP its been running for 1 hour and no caking so far Edited May 11, 2009 by hondo

[pyrogeorge]

How will I know when my charcoal becomes wet?

charcoal must be airfloat..just take a small ammount in your hand and press it..if it sticks together like a "flake" your charcoal is wet.

[TYRONEEZEKIEL]

ok awesome.. Yeah, my charcoal doesnt do that at all.. I really think that it is my KNO3

[Swede]

How are you storing it? In high-humidity environments, the best way is in a large plastic bag, which is then inserted in a good bucket with a lid, like a 2.5 or 5 gallon paint bucket. Put two "walls" between the nitrate and the outside world. I tend to do that with all my chemicals, and it keeps them free-flowing and dry.

[TYRONEEZEKIEL]

I have it in a plastic snap top tupperware container with several silica gel packets in with it. But, I dont believe that is enough to combat the constant 90%+ humidity in Texas.