My homemade black powder

[almar]

I added up my last six batches' yields, and broadly speaking when I crush and sieve the sizes I get are:
>15# - first pass about 60% but I re-grind until it all goes through the 15# sieve.
FF 15-20# - 28%
FFF 20-40# - 28%
FFFF 40# -100# 25%
Fines < 100# 19% go into next batch of pucks (except a teaspoonful for a poof test).

I chose to design for a 500g mill batch, which limits the size of risk if something goes wrong. I have been putting in about three to five hours work to make each batch. This means that at the end of processing a batch, I have about 160 g of FF and 160g of FFF, the two important sizes for most of us.

If I could buy it, I would be better doing so.

I am trying a few different puck breaking and grinding ways, and they don't seem to make much difference. Last time I tried a wood-chisel to 'cut' them on a hardwood block but it didn't improve yield. Next time I plan to use a sharp edge to slice before drying the pucks, and spend more time to reduce them below coffee bean size with the sharp edge, before drying.

almar, your PID controller uses a mathematical algorithm rather than an 'on-off outside a plus and minus switching temps' like a bimetallic strip switch. I am thinking how a better screening method or sizing choice could improve my yields or reduce the input effort.
I am considering targeting 15- 30# for FF, increasing its share, and re-pucking 4F as well as fines. 3F is good, but 2F needs more bulk as its used for the 100m heavy charges, ie three times as much powder per shot as a 3F pistol charge and 45% more than a 3F 50m charge in a rifle.
That means I need some different sieves for the deck.

Ive been secretly trying out a manual grain mill with 2 rotating cylinders that are covered with rotating spiked cylinders. It is typically used by people who crush their malt. It is adjustable to different distances between the cylinders. Instead of grinding or smashing the pucks, they cut and crush. I have very little dust compared to the coffee grinder. But the thing requires some modification to attach it firmly to a surface and requires a few passes at different distances between the cylinders to get it to fffg size. Its much faster and does a better job than a coffee mill or hammer but I am just testing it for now.

[almar]

[QUOTE=indian joe;5287068]

...also someone mentioned spotting of moisture ? I couldnt get an even mix unless I used too much water - ended up I damp the mix, then form it into balls by hand (almost tennis ball size) then I grate those balls back through a wire screen into a pile that I put into the pressing die - gives me a thorough mix = no moisture spotting without getting it too damp .

Yup! I pass the mix through a 20 mesh screen after adding the water, I thought I mentioned that but I didn't, must have been in a PM.

[ChrisPer]

also someone mentioned spotting of moisture ? I couldnt get an even mix unless I used too much water - ended up I damp the mix, then form it into balls by hand (almost tennis ball size) then I grate those balls back through a wire screen into a pile that I put into the pressing die - gives me a thorough mix = no moisture spotting without getting it too damp .

I was moistening like blending butter in flour - using fingers (in nitrile gloves) to rub through the mixture and break lumps. Mixed results. I will try the sieve.

Ive been secretly trying out a manual grain mill with 2 rotating cylinders that are covered with rotating spiked cylinders. It is typically used by people who crush their malt. It is adjustable to different distances between the cylinders. Instead of grinding or smashing the pucks, they cut and crush. I have very little dust compared to the coffee grinder. But the thing requires some modification to attach it firmly to a surface and requires a few passes at different distances between the cylinders to get it to fffg size. Its much faster and does a better job than a coffee mill or hammer but I am just testing it for now.

Cool almar. Glad I learned this before I put in the effort on mods to the ceramic coffee grinder. I have a silversmiths geared rolling mill for plate and wire, very easy to adjust spacing. I could CNC new bronze rollers with evolute tooth profiles... no, not really. But craftsmen I dream about on Youtube could.

[ChrisPer]

My sand-filled resin pistons are falling apart. Might be time for turned - or cast - aluminum ones.
Part of the problem is the toothy top of the jack. maybe time to set up a different, wider and smoother top on it to self-centre the pistons.
Another part is the sand filling settles, so there is a bit of pure resin at one end of the piston which is susceptible to chipping.

[almar]

[ChrisPer]

Nice! Thank you for that.

[HamGunner]

Managed to fire a cylinder full of the Sassafras powder today. Same charge (20 gr.) and projectile (80 gr. ball) and home made felt lubed wad as with my other two powder tests with my 1851 .36 cal. Pietta Colt Navy. My Black Willow came out fastest at 650 fps, this Sassafras came out second at 625 fps, and the Carolina Buckthorn came out third at 615 fps. More tests might show slightly different velocities.

From what I saw with the accuracy, Sassafras is the top dog. Very fine accuracy, although the impact of the group was lower for some reason. Both the Black Willow and Carolina Buckthorn gave around 2 1/2" groups at 20 yards, but the Sassafras was much tighter at around 1 1/2" inch group.

Sassafras was almost as dense as the Black Willow, where the Buckthorn was a bit lighter for the same volume.

I only made up a small 1/2 Lb. batch of the Sassafras so I think I might give it another try. I certainly do like accurate powders and I like the fact that I can get a truck load of Sassafras about anytime I want around my neck of the woods.

[mmb617]

The bottleneck in my system is breaking the pucks down so they go through the ceramic grinder - making thinner pucks I use plastic spacers in the pressing die and aim for 1/4 inch or no more than 3/8 thick - if you go to half inch theres a lot of big hard chunks that wont feed in the grinder . I tried breaking the pucks before they dried but got too much fines .

I'm new at this but I'd like to add my input for whatever it might be worth as I'm doing a lot of experimenting. So far my finished product has worked well and I'm trying to find the easiest and fastest way to get to that point.

I quickly found that too thick pucks are hard to break down into sizes to fit my grinders. What seems to be working well for me is 30 grams of green mill in my 3 inch puck press which gives puck thickness averaging right around 4mm, so roughly between 1/8 and 3/16 inch thick. I use dividers to press 3 pucks at a time which tends to make some pucks lopsided in thickness but that hasn't been a problem.

I've been pressing my pucks then putting them in a dehydrator for 48 hours before breaking them up. I grind them in stages. First I use a 3 inch pvc pipe end cap and a brass punch to get pieces small enough for my first grinding which is in a cheap hand powered ceramic coffee grinder. From there they go in my little DC powered grinder (also with ceramic burrs) set on the next to finest setting. I then screen and anything left on top of the #20 screen gets run through the power grinder again. Anything left on top after that grinding I consider to be 2f. The screen under the #20 is a #40 and whatever stays on that screen is considered to be 3f. Anything that falls through that screen I recycle at present but I'm getting a #60 screen which I intend to use for what I'll consider to be 4f.

It sounds more labor intensive than it is and I enjoy the work so I don't think I'll have any problem producing all the powder my son and I need.

As I said it's all new to me so I'm playing around a lot. I understand the danger of having spilled powder dust on the floor and tables in the shop so I always sweep up after a session. Normally I just throw that dust on the lawn but yesterday I had a bunch of it in the dustpan and having never done any kind of flash test I got an idea. I know the real test it to lay out a line and light one end to see how fast it burns but instead I just threw a lit match into the stuff in the dustpan (outdoors of course). Poof! It was gone in one quick and rather large flash. Pretty neat actually.

I'm presently using my homemade screens and get too much spillage so I was looking for an alternative. I ordered a set of nesting scientific screens that I think will solve that problem. They were pricey but I think they'll turn out to be a good investment long term.

I have a lot more money invested in equipment than I thought I would, so I'll need to make a lot of powder to get back my investment monetarily, but who can put a price on the enjoyment I get from this and the degree of self-sufficiency it gives me.

[mmb617]

I forgot to add one thing I learned already. My first batch of powder worked fine in my flintlocks but didn't flow worth a crap. I could not get it to flow from my flask to my powder measure. Once loaded it fired every time but getting it into the gun was problematic. I realized that the problem was too many fines mixed in as I hadn't been shaking my screens aggressively enough to get all the fines through the #40 screen. Now I shake them much harder and the stuff I call 3f flows really well.

Because my homemade screens are shallow some powder escapes with such aggressive shaking which is why I think the new set of screens I ordered will take care of that problem. The screens all nest into each other and there is a lid on top of the stack. The entire assembly is 304 stainless steel. My research indicates that 304 stainless steel is suitable for use in explosion proof equipment so it should be safe.

[maillemaker]

A little tip: When adding the moisture to the mill powder before pucking, passing the mix through a 20 mesh screen before pressing does a great job at evening out the mixture.

I work in small batches about the size of my fist, and I mist distilled water onto the spread-out meal with a spray bottle. I then use a plastic Bondo spatula to "slice and dice" the pile and mix it all together. It's like making lines of coke in the movies. Seems to be pretty consistent and I don't have problems with over-wetting anymore.

The barley mill looks interesting. I wonder if it is spark-safe?

Steve

[almar]

I work in small batches about the size of my fist, and I mist distilled water onto the spread-out meal with a spray bottle. I then use a plastic Bondo spatula to "slice and dice" the pile and mix it all together. It's like making lines of coke in the movies. Seems to be pretty consistent and I don't have problems with over-wetting anymore.

The barley mill looks interesting. I wonder if it is spark-safe?

Steve

Ah i knew i put that in here somewhere. Yeah i do the same as you i just added that as another step because i add so little water for 1 lbs.

I don't see how it can spark. No metal touches other metal. I am just testing it for now i have to figure out if its a good tool for this or not.

[HamGunner]

I then screen and anything left on top of the #20 screen gets run through the power grinder again. Anything left on top after that grinding I consider to be 2f. The screen under the #20 is a #40 and whatever stays on that screen is considered to be 3f.

I do about the same thing with wooden home made screen frames and also with #20 mesh and #40 mesh stainless steel screens. I regrind anything remaining on top of the #20 mesh if they also do not pass a small hand held #12 kitchen screen and save the rest on top of the #20 for approximate FFG size, but I do not usually save all that much of the FFG. My screen frames sit flat against each other so there is no spillage unless I let some jump over the top of the 3/4" top frame.

I use a small 60 ml measuring cup for my puck layer amounts and I fill it level to the top, so that makes it more like 80-85 ml per layer in my 3" die and compress that in my 12 ton press. I took the hint of Almar and placed a mark on my aluminum mandrel so that I can tell that the compressions all stay uniform. I place four layers into the 3" die so they are not as thick and easier to bust up. I grind them through a ceramic burr hand grinder.

I compared busting up after drying to busting up right away and I really could not tell much difference in the amount of fines, so I now bust the pucks up right away and grind and dry the granules, which takes less time and should give a more uniform dryness.

[Vettepilot]

@HamGunner: That Sassafras you tested... granulated or compressed powder??

Wonder why Almar had poor results with it?

Anyone have a source on that grain mill? I think I'd like to know more about that.

Thanks!
Vettepilot

[HamGunner]

My Sassafras was milled and compressed and busted up and ground just like all my other powders. The charcoal was a dark brown color and the ash content measured 2.6% and produced a nice light colored ash. Weight of the powder was just one grain less than my Black Willow using the same volume measurement.

I will do some more shooting for accuracy with all the powders that I have made so far, but the Sassafras certainly looks promising for tight groups, although they shoot at least 6" lower for some reason and eat a hole at the bottom of the target.

My Carolina Buckthorn left little ash as well, but the volume weight was a bit lower. Velocity just a bit lower but the accuracy was about the same as my Black Willow.

Like I said, I need to do some more shooting when I have the time to really sit down and play for a while. I will likely find the proper volume of each powder to load in the chambers of the revolver that will give the best accuracy. That will likely show me better useful data than just testing a set weight charge, which has been 20 gr. in the .36 cal. Some of the types of powder charges of 20 gr. are compressed more than others so I hope to improve accuracy by finding the sweet spot where the revolver likes to be loaded. Velocities might change, but hopefully I can make them all shoot accurately.

[SeaMonkey]

Here are some Malt Mills from various vendors.

More expensive than the Coffee Grinders but perhaps well worth it.

Although, this model is nicely priced. I wonder if it would do?

Almar may be on to something here.

[Nobade]

I got my copy of Brett Gibbons' new book last night, "Like Fire and Powder" about making gunpowder and his quest to make "RFG" - Rifle Fine Grain, the powder the British developed to use in the '53 Enfield. I made it through the chapter on purifying nitrate, something very important to powder production and AFAIK not mentioned here yet. I would highly recommend this book to anyone interested in producing top quality gunpowder, Brett has done a huge amount of work that we can all benefit from.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[almar]

Thank you Nobade.

Dont get too excited about the grain mill. It works, yes but it can be a real pain because the cheap ones are meant for small particles and have a limited range of spacing. If you don't get the grain size small enough it will not work and its a real pain to unload it all and start all over.

The big ones that also mill corn have 2 inch rollers and are adjustable from a full 0.00 to 0.200. But they are over 200$ (at least the one i could find quickly) might as well stick with the coffee grinder at that point. One option would be to make really thin pucks like 0.15 in. or so, another to see if i cant modify it to increase its range. Its on the back burner for a little bit. Gotta figure out the sassfaras out first and other little things like reaming my cylinder throats to proper dimensions.


https://www.monsterbrewinghardware.c...Mill-9p100.htm

[SeaMonkey]

After reading again to refresh memory of how the Swiss Powder is pressed with their Roller Press, which is unique, questions come to mind.

Page 19 of the Swiss Powder Booklet (page 20 of the pdf.}

Why couldn't the pressing be accomplished between two flat plates with the loose powder essentially pressed into a thin "pancake" without need for a puck cylinder?

Extract from the booklet:

This roller type powder press was installed in the Swiss black powder plant in
1978, replacing the traditional vertical plate powder press.

This roller (Laminoir) type powder press is unique to the Swiss bp plant. The
only such powder press in operation.

Figure 26 shows the feed end of the powder press.

Broken down mill cake is fed onto the slowly moving rubber belt in a specified
thickness. The powder then passes under the roller. The roller operating at up to 30 metric
tons of pressure.

Figure 27 shows the pressed powder end of the press. After passing
beneath the roller the powder cake will break off and drop into the collection box.

The cake produced by the powder press ranges in thickness from I cm.
to 0.5 cm. depending on the type of powder being pressed.

Powder from the wheel mill is low in density and lacks the required degree of
cohesiveness required in a propellant powder. During powder pressing the volume of the
powder is reduced by about 35 to 40% of its original volume as it comes from the wheel
mill. The pressing operations both compacts and consolidates the powder. This imparts a
high degree of mechanical strength in the pressed powder.

The press densification and consolidation of the powder does not require that the
powder be held under great pressure for any length of time, as would be seen in the
typical plate press. Imparting mechanical strength in the powder comes about after the
water has begun to evaporate from the pressed powder cake. As the press cake is exposed
to air there will be a slight loss of moisture and a bonding within the mass that provides
the desired degree of mechanical strength to the powder.

It seems that exposure to air during the pressing is advantageous as it permits the moistened powder to dry somewhat and strengthen the powder for the corning process.

Their pressing thickness of 5mm to 10 mm seems a bit thick though for what we're striving to accomplish.

Has anyone tried pressing without a containment cylinder?

[almar]

After reading again to refresh memory of how the Swiss Powder is pressed with their Roller Press, which is unique, questions come to mind.

Page 19 of the Swiss Powder Booklet (page 20 of the pdf.}

Why couldn't the pressing be accomplished between two flat plates with the loose powder essentially pressed into a thin "pancake" without need for a puck cylinder?

Extract from the booklet:


It seems that exposure to air during the pressing is advantageous as it permits the moistened powder to dry somewhat and strengthen the powder for the corning process.

Their pressing thickness of 5mm to 10 mm seems a bit thick though for what we're striving to accomplish.

Has anyone tried pressing without a containment cylinder?

lets be mindful of the production efficiency needs of large scale producers, I wonder if that is just to make things faster? Or maybe there is more to it...

On another note, I weighed the remaining sassafras milled powder and added the required amount of charcoal and Sulphur to bring it to 75-15-10 and it has now milled for another 6 hours on top of the previous 9 hours. At a total of 12 hours, it burned cleaner but more like a match. At that point I didn't have much hope for it. I tested it now after a total of 15 hours and its much cleaner and fast. Good! it may need a different charcoal cooking regimen than willow too. I think I can make something good of this wood with time.

One thing with ceramic media is that its lighter than lead so although it doesn't wear like lead it has less of "smashing" effect than lead. So it can take more time maybe. A give and a take.

[ChrisPer]

The excellent idea of pressing thin but unconfined is covered in a historic arms blog (will find the link later) that has a series of detailed descriptions of C19 powder manufacture.
The factory described put thin layers of dampened powder between large copper plates, stacked up to a foot-thick deck, then put in a press.
The problem for us is that you need a VERY big press. I need 5 tons to get 3500psi for a 2-inch diameter die, checking my calcs a foot-square die calls for 150 tonnes. And it has to be delivered evenly over a large area - the upper and lower press plates would need a half-tonne of cast iron.
Just between you and me, I can't lift that even after a steak dinner!
The likely solution is as the Swiss do, a roller. The meal is still between plates, but the roller only needs to deliver a tenth the pressure. HOWEVER, you still need the press time - which needs power feed through the rollers at a very slow rate.

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Update: The link to the pressing description
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