Making Black Powder with a Ball Mill

Making Black Powder with a Ball Mill

Written by Harry Gilliam

Topics: How to Make Fireworks

You can get potassium nitrate for making black powder really cheap, if you can find prilled or hard nitrate. “Prilled” nitrate comes in little spheres, around 1 mm or less in diameter.

Make Black Powder Using Cheap Potassium Nitrate Prills

How to Make Black Powder Using Coarse Chemicals

Prilled nitrate is too coarse to use as-is in making black powder and other fireworks, but once you grind it up to about 200 mesh, it’s perfect.

Keep in mind that potassium nitrate, like most oxidizers commonly used in making fireworks, eventually absorbs enough water to get more or less petrified. But it’s still good. You just need to grind it up into a fine, fluffy powder again. It never goes bad, even if it’s gotten wet or has been stored for years.

So learning to grind/mill hard chemicals is one of the routine tasks that all fireworkers need to master.

We routinely recommend two ways: coffee milling and ball milling. Both ways have advantages.

To grind a single chemical (vs. a mix like black powder) using a ball mill, fill your mill jar half full of hardened lead or brass grinding media, and 25% full of potassium nitrate. Turn the mill on and come back in an hour. Your nitrate should be light and fluffy. If not, continue grinding it ’til it’s fine powder with no chunks or grains.

But guess what?

The good news is that sometimes you don’t need to do anything extra like pre-milling. Here’s a quick and dirty video I made. It shows how you can even use coarse chemicals and primitive equipment to make black powder just as good as any commercially made BP.

Making Black Powder with a Ball Mill

Just so you know what’s going on. This is me in my backyard. I am using a homemade ball mill I’ve had for 20 years, and Skylighter’s ½” antimony-hardened lead balls.

Check out my fancy-dancy mill jar! It’s a one-gallon plastic mayonnaise jar stuck inside a large coffee can for reinforcement. I actually have to tape the screw top on it so it doesn’t come off while it’s turning!

This is down and dirty, almost totally homemade equipment. You do NOT need to be fancy or sophisticated (which I sure as hell ain’t!) to make great black powder which performs as well as anything you can buy.

To make this black powder, I’m using Skylighter’s el cheapo, prilled potassium nitrate–the cheapest stuff we have. Everything you see is right out of the containers—no pre-grinding or screening. The point is, look at how quick and easy it is to make black powder using really coarse potassium nitrate without having to spend any time making it finer first.

When the black powder’s finished, you’ll see me using my busted up old bucket screen to separate the lead balls from the new black powder. (You will NOT be impressed!)

Remember these magic proportions when you’re making black powder with a ball mill:

- Fill your mill jar half full of hardened lead balls (or brass)
- Fill half of the remaining space with your 3 chemicals
- Leave 25% empty “head space”

Got it? 50% lead balls, 25% chemicals, 25% air.

These proportions are the “sweet spot” that guarantees that your powder will be good AND that you can do it in the shortest amount of time (typically 3-4 hours).

Troubleshooting: How to Prevent Pitiful Powder Syndrome

From time to time, folks call who have been seriously afflicted with Pitiful Powder Syndrome, an acute black powder deficiency known to cause all manner of fireworks failures and hair-pulling.

Their symptoms are always the same: their ball-milled black powder doesn’t work.

So, the first thing we do is get him (the “hers” are never afflicted) to describe how he made it.

Every time… I mean every single time, the victim’s PPS can be traced to making the black powder a different way than the simple process shown. (Or, as we were warned in kindergarten, by not following instructions—a manly trait.)

Here’s how people most commonly get infected by Pitiful Powder Syndrome:

Not using enough milling media: Always fill your jar 50% full of grinding media.

Using media that’s too small: Use ½” for 1 gallon mill jars or smaller; ¾” for larger mill jars; for 5 gallons or larger, use 1-inch.

Using lightweight grinding media: You want lead or brass. Both are heavy enough, but will not spark or cause an accidental ignition. Do not use steel or ceramic. They can cause another syndrome—death.

Milling for too short a time: run your mill for at least 3 hours. You probably don’t need to run it longer than 5 hours. Milling longer than that will probably not improve your black powder significantly.

Using different chemicals: Standard black powder is made with potassium nitrate, sulfur, and charcoal. Switching or omitting chemicals is a common cause of pitiful powder. Do not waste time and money by second guessing these chemicals.

Remember: making black powder this way is a tried and tested method, perfected for hundreds of years by people who learned more about it than you and I ever will.

Want to Get a Black Powder Making FAQ?

If you’re new to making black powder we made up a Black Powder “Cheatsheat” for you. This would be a good thing to print out and keep in your fireworks-making notebook or pinned to the wall of your shop.

The Black Powder Cheat Sheet will help you make sense of the different black powder, legalities, grades, sources for store-bought BP, and a comparison of the most common ways of making BP.

  • Understand the legalities of making black powder
  • Discover the different methods for making black powder
  • Cut through all the confusion surrounding grades and particle sizes
  • Learn the best type of black powder for each fireworks application
  • Find the best places to buy commercial BP

Just click here and give us your best email address and we’ll send it to you.

23 Comments For This Post I'd Love to Hear Yours!

  1. dertik says:

    hi) i have a question /// how i may change composition colored fountain because i doesnt found red gum in my country and other analog in ukraine i doesnt found red gum please say me how me made green fountain without red gum or what i may use . i make red rountain (amonium perhlorate30 stroncium nirate30 Ti and rosin 1%and 1%coal )but this fountain have small
    height what mixtures of metal i may use becouse i want large sparks
    thanks

  2. Randy says:

    Good article Harry,

    Now you should investigate the alternative way to make superior Black Powder.

    Those prilled Potassium Nitrate crystals will dissolve in heated water and so there’s no need to pre-mill.

    Your mill would be needed to mill only the sulfur and (Willow) charcoal together till they are of a fluffy black almost liquid like consistency. (Note- It’s easier to fill the milling jar for this if your charcoal was made ahead of time by milling).

    To make 500gram batch- Dissolve 375 grams of the prilled Potassium nitrate in 300ML of water- the powder will dissolve as the pot is heated.

    When the liquid in the pot turns clear-no white crystals- add 125 grams of the milled sulfur/(willow)charcoal.

    It takes a lot of mixing to get the fluffy powder mixed in. If the heat is too high, the mixture will begin to boil before you get it mixed- remove from heat to prevent it overflowing the pot.

    It’s important to keep the Potassium Nitrate dissolved so don’t turn off the heat till the mixture becomes a shiny black fluffy mass as you’re mixing.

    When mixed, turn off the heat and allow the mix to cool for half an hour.During this time, you can get the denatured alcohol out of the freezer and measure out 750 ML- I use a graduated beaker for this.

    I pour this alcohol into a stainless pot with lid and place back into the freezer to maintain the superchill until the half hour has passed.

    Next you’re ready to get the alcohol in stainless pot back out of the freezer and place next to your BP pot.

    Turn on the heat and this time you can turn it up high to get the mix boiling again quickly- the black shiny fluffy mass again- and when it reaches this state simply pour it into the superchilled alcohol and stir to cool the powder down fast.

    You’ll need a spatula to clean out the BP from your pots during this process.

    When the BP and alcohol has cooled in the stainless pot with lid, you’re ready to place a cloth into your boiling pot and pour out the BP “sauce” into it, gather the ends of the cloth and pick it up and allow the alcohol (and the water that was used to dissolve the Potassium Nitrate), to drain out of the powder.

    With gloved hands, squeeze out as much alcohol as deemed necessary with practice, then tha BP is ready to be pressed in to cakes and allowed to dry.

    When dry, the cakes are ready to be broken up and screened to the different mesh sizes desired. This is where the powder becomes explosive so empty your screenings often into storage containers.

    The 750 ml of alcohol used in this process (The CIA Method) can be recycled by pouring what was squeezed out before pressing into cakes, into glass jars with lids,(to control evaporation),and allowed to sit undisturbed for a couple of days.

    You’ll see the waste solids have settled onto the bottom and the clear alcohol, water, and dissolved Potassium Nitrate are on top.

    Scim this liquid and place in an empty alcohol can and place in the freezer for a couple of days.

    Pour out the recycled alcohol into another can using a funnel and paint strainer. The strainer will capture the water which is now ice, and the Potassium Nitrate which is now wet powder.

    Spread this out onto paper to dry and now you even have some recycled Potassium Nitrate to use for a future batch of BP.

    • M. Fehlinger, PhD says:

      Dar Randy,

      Your method is very dangerous. In this case the danger does not come from the BP but from your method.

      In chemistry labs (I have been working in labs over 10 years), it is strictly forbidden to store flammable liquids (E.g. alcohol) in freezers and refrigerators that are not certified for laboratories.

      Reason is, fumes from volatile liquids do collect and cause major explosions. This happens over time even when containers are closed. Normal freezers and fridges contain electric circuits that produce sparks in the interior, sometimes. At my university, several fridges had exploded some years ago before this measure was established.

      So my advise here: Do-not-do-this. Or buy a lab-certified freezer.

      Kind regards,

      Matthias

  3. JOHN oATMAN says:

    iS SULFUR REALLY NESASSARY OR WILLmilled knitrate and charcoal burn just as fast. Thanks JOHN

  4. EVIL KID says:

    HOW DO U MAKE DRAGON EGGS OR CRACKLING BALL ?

  5. Tyler says:

    Another great video. How do you store the lead/brass balls? Looks to me like they might have enough BP on them to go boom.

  6. James says:

    Does that mean we should NOT use Alumina balls for grinding media?

    • Dr. T says:

      I ran several parallel tests with lead/antimony balls and ceramic (alumina) pellets. Both worked, but the alumina media took about 50% longer to get the same results.

      The primary idea behind not using ceramic media is piezoelectricity – ceramics can give off sparks when struck. I haven’t seen any problems or personally heard of any, but the possibility exists, and lead shot works better anyway, so I decided not to risk it any more.

  7. David says:

    1. Nice shirt-change there across
    3 hours. Didn’t think we’d notice?

    2. The meal needs to be dampened
    and compressed then broken into granules. How do you prefer to do this? Or do you use the raw meal?

    A quick demo lighting off a teaspoon unconfined would be good.

  8. Art says:

    Is there any way to turn the talcum like powder in to coarser grades ( FFFG, FFG)? i would like to experiment with different powder types in my shells

  9. William says:

    I am from Delaware and I used to walk the trails and fish in the Brandywine near DuPont’s old powder mill. There are still huge rollers and machine parts scattered along the creek due to the many explosions (8 in all, I believe)when they made gunpowder at their factory. I don’t know how many people in all were killed, but one of the Duponts was blasted to smithereens when he tried to put out a fire in the milling room. They were professionals!

  10. Ralph says:

    I do all my ball milling under roof and open on all sides behind my out building and also surrounded by logs

  11. scott says:

    I have a pit dug inplace of the 200 feet or a sand dirt bum around the mill works.

  12. scott says:

    Great job No nonsence KISS method
    Don’t get me wrong I love your videos but I can’t help thinking of the Red Green Show. Keep it up
    Thanks

    • Reggie says:

      I would have LOVED to see Red Green come up with some BP making ideas! BP and duct tape; the handy man’s secret weapon!

  13. Jeff Evans says:

    well done mate I have seen people with mills in garages,patios,even in basements and wondered? Anyway great job again and for a “bottle washer” you do ok,Jeff

  14. Clarence says:

    I like your style Harry.

    Would love to see what you have for a mill there. We all have to come up with our own contraptions.

  15. Joe Phelps says:

    Great video Harry!

    My home-made mill uses a vibratory case tumbler container on it’s side (built-in lift bars) with a 30 rpm geared motor and ¾ inch brass balls.

    In four hours I get 2 pounds of awesome powder using your charcoal and potassium nitrate.

    Thanks!

  16. Joe says:

    Liked that…if I put me ball mill 200feet away I’d be in the next village ha ha.

    • Tom says:

      If you don’t put it far enough away you might wind up in the next state or country. At least parts of you. Safety first and foremost!

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