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Black Powder Basics
and Manufacture
Black Powder is the backbone of
pyrotechnics. After all, it's Black Powder that gives
fireworks the smell we all love so much. Black Powder
is the main ingredient in a variety of firework and
rocket formulas. You can easily make your own high quality
Black Powder with just a few chemicals and a Ball Mill.
Black Powder Basics
Black Powder is also known by a couple
of other names. The most common, is Gun Powder. Black
powder is produced in large quantities commercially,
and sold in small 1 pound containers, mainly for use
in antique Black Powder guns. It is also normally sold
in different granulations, and they indicate how fine
the Black Powder is granulated by how many "F's"
they put on the container. Coarse granulations are called
"FG or FFG" (aka "1Fg" and "2Fg").
Finer granulations are "FFFg and "FFFFg"
(aka 3Fg and 4Fg). The more "F's", the finer
the Black Powder... and the finer the Black Powder is,
the faster it burns. Small (fine) granulations burn
faster and are used in small bore guns, where larger
(coarser) granulations, are used for larger bore guns
& cannons... and for launching Aerial Shells out
of mortars. Using a finer granulation for these jobs
puts too much strain on the gun (or shell or mortar)
because the powder burns much faster and creates a fast
pressure increase that could damage whatever you're
trying to launch, or the gun/mortar itself. Coarser,
granulated Black Powder that is used in mortars to launch
shells, or in Roman Candles to shoot out stars, is sometimes
called "Lift Powder". When Black Powder isn't
granulated, and is in a super fine powder state (similar
to that of Talcum Powder) it is called "Meal Powder".
Just to confuse things even more, any granulated Black
Powder is also sometimes called "Grain Powder".
Smokeless Powder (Pyrodex, etc.) is not
to be confused with Black Powder. It is actually Nitrocellulose,
and cannot be used in place of Black Powder.
Now, why they needed 5 names to describe one substance
is beyond me, but just keep in mind that Black Powder,
Gun Powder, Lift Powder, Grain Powder, and Meal Powder
are really all the same material. 30 years ago (when
I was 13), I sat picking the raisins out of Oatmeal
because I thought Meal Powder was just finely powdered
Oatmeal. Needless to say, the rocket engine I was building
didn't work, as Oatmeal doesn't have quite the kick
that Black Powder does. On the other hand, Black Powder
makes a terrible breakfast.
Anyway, as far as fireworks are concerned,
Black Powder is used both in its finely powdered form
(Meal Powder) for coating starts and for mixing in other
pyrotechnic formulas, and in its granulated form (Lift
Powder) for launching shells out of a mortar, or stars
out of a Roman Candle.
The formula for Black Powder is 75% Potassium
Nitrate, 15% Charcoal, and 10% Sulfur, and like all
formulas, it is measured by weight only.
However, unlike many pyrotechnic formulas, you just
can't mix these chemicals together and expect to have
Black Powder. The mixing process for Black Powder is
just as important as the formula. Black Powder MUST
be made in a Ball Mill to work properly.
A Ball Mill is a rotating drum with dozens of lead balls
inside. The 3 chemicals are loaded into the Ball Mill,
along with the lead balls, sealed shut and allowed to
rotate for anywhere between 1 hour and 24 hours. As
the Ball Mill rotates, the lead balls will crush the
chemicals together, forcing some of the Potassium Nitrate
into the pores of the Charcoal and Sulfur. At the same
time, the entire mass will be reduced to a super fine
powder. The longer the Ball Mill runs, the stronger
the Black Powder will be. A general rule of thumb for
all pyrotechnic mixtures is " the finer the powder
is, the faster it will burn ". ONLY lead
balls can be used in a Ball Mill as they are completely
non-sparking. ONLY Black Powder can be mixed
in a Ball Mill. Other pyrotechnic mixtures such as Flash
Powder, etc. CAN NOT, as they are too sensitive
and will explode. Individual chemicals however, can
also be Ball Milled into a fine powder, but the mill
must be cleaned before this is done. Ball Mills, complete
with hardened lead balls are available from United Nuclear
by Clicking
Here.
Once the mill has run for a while, it
can be opened and the lead balls separated from the
fine Meal Powder. As we'll show you below, this Meal
Powder can now be used to make all the other forms of
Black Powder for use in fireworks.
Black Powder vs. Flash Powder
A lot of people ask which is stronger,
Black Powder or Flash Powder... or if Black Powder can
be used in Salutes (exploding fireworks). In short,
there is no comparison. Flash Powder is a high explosive,
a shattering explosive. It converts to a gas so fast,
that objects near it, and containers that hold it cannot
move out of they way (or vent) fast enough to release
this gas, so they are destroyed into fragments. Black
Powder is a low explosive, a heaving explosive. It converts
to gas much more slowly than Flash Powder, and generally
pushes things as opposed to fragmenting them. If Black
Powder is used in a small Salute like an M-80, it will
just make a loud "pop", and push out the end
plugs. Flash Powder in an M-80 will make a loud explosion
and fragment the tube into small pieces. Flash Powder
burns so much faster than Black Powder that in larger
Salutes, it doesn't even matter if you've got end plugs
on the tube at all, it will still detonate and fragment
the Salute, even with 2 open ends. You can NEVER
substitute Flash Powder for Black Powder or vice-versa.
If you were to use Flash Powder to launch a shell out
of a tube, or a bullet out of a gun, it would barely
move the shell or bullet, and completely destroy the
mortar or gun, most probably injuring the operator.
Manufacture
You will need 3 chemicals to make Black
Powder, they are: Potassium Nitrate, Sulfur and Charcoal.
Stay away from very low grade materials like "Dusting
Sulfur" and Bar-B-Que Charcoal Briquettes. The
Charcoal you use in a BBQ is not pure Charcoal. It contains
other materials and chemicals that are designed to keep
the material burning evenly and for a long time, but
it will make lousy Black Powder. If you use low quality
chemicals, you will undoubtedly get low quality Black
Powder.
The following is the standard formula
for Black Powder:
| Black Powder |
|
|
Potassium Nitrate
|
75 % |
|
Charcoal Powder
|
15 % |
|
Sulfur
|
10 % |
If you are not familiar with measuring
& percentages, see the Basic
Techniques section first.
Open the lid to your Ball Mill and add
the following: 150 grams of Potassium Nitrate,
30 grams of Charcoal Powder, and 20 grams of Sulfur
( if your lead balls are not already in the tumbling
barrel, go ahead and put them in now ). Remember that
ONLY lead balls can be used because they are completely
non-sparking. When complete, this will make 200 grams
of Black Powder ( a little under 1/2 pound ). You can
make larger or smaller batches, just keep the percentages
of all the chemicals the same. You MUST use an accurate
scale to weigh your chemicals, preferably one that is
accurate to 1/10th of a gram.

With all 3 chemicals and the lead balls
inside, put the lid on the tumbling barrel and seal
it, then set it in the Mill. Turn on your Ball Mill
and let it rotate for 2 to 4 hours. As the Ball Mill
rotates, the lead balls will crush the chemicals together
and reduce them into a super fine powder. The longer
you let it grind, the stronger your Black Powder will
be. Let the Ball Mill do its grinding in an uninhabited
area, not in a place like your bedroom. Although the
chance of accidental ignition is very remote, it is
wise to put your mill in the garage, or better yet,
outside to do its work.

At the end of a couple of hours stop the
mill. Lay out a sheet of paper ( newspaper will work
fine ). Open the lid to the barrel, and dump the entire
contents ( lead balls and all ) into a spaghetti strainer
over your sheet of paper. The strainer will catch the
lead balls and with a little shaking, all the Black
Powder will filter through onto your paper sheet. When
Black Powder is in a fine "dust-like" state
like this, it is called "Meal Powder". The
Meal Powder you just made can now be used as-is in a
variety of formulas and projects. By adding a little
water and Dextrin to it, you can easily make Black Match
Fuse or Quickmatch. See our section on making Black
Match Fuse & Quickmatch.

Lifting Powder
There are some applications where very
fine Black Powder ( Meal Powder ) will not work well.
If you're going to use your Black Powder to launch shells
out of a mortar, or for small cannons, it will have
to be granulated first. Black Powder that is granulated
and used for launching shells and salutes is called
"Lifting Powder". The procedure for making
lifting powder is easy, but it sometimes takes a few
tries to get it perfect. Basically all we're going to
do is to add a little of a water soluble glue ( Dextrin
) to the Meal Powder, mix it well, get it a little damp,
and push it through the spaghetti strainer again. This
will produce small granules of Black Powder perfect
for launching shells or anything else. The whole trick
to this is not to get the mixture too wet, or it will
become gooey and just turn into a big mess.
To convert your Meal Powder into Lifting
Powder, take 100 grams of Meal Powder and mix in 10
grams of dextrin. A good way to mix them is to put the
mixture in a plastic container with a snap-on lid and
shake well. Pour the powder through the spaghetti strainer
again, this will break up any lumps in the dextrin.
Now place the Meal Powder/Dextrin mix back in your plastic
container and add just a little water. This is where
experience really pays off. The idea here it to get
the mixture damp and not wet. What can be deceiving
is that you're adding water to a very fine powder, so
it's going to take several minutes of mixing just to
get the powder to begin to absorb any water at all.
Add just a little water at a time, mixing thoroughly.
As the powder begins to take in water, it will turn
a bit darker in color. You want the mixture to be damp
enough to where if you take a handful of it and squeeze
it tightly, it will just begin stick together. You do
not want to get it too wet. If you do, it will not go
through the spaghetti strainer and will just clump up
on the bottom, or not go through the holes at all. If
disaster strikes and you have added too much water,
you can always just add some plain Meal Powder to the
mix to dry it out.
Just FYI, adding the water also increases the strength
of the Black Powder by allowing some of the Potassium
Nitrate to dissolve and be absorbed into the pores of
the charcoal particles.
Once the mixture is damp, lay out another
sheet of newspaper and dump the mixture into the spaghetti
strainer. Using a wooden or plastic spoon ( or your
hands if you don't mind getting messy ), rub the mixture
through the screen allowing the granules to fall onto
the newspaper below. The Lift Powder you're making will
have to dry for a few days before it can be used, so
make sure to spread it around on the newspaper so it
will dry more quickly.
If your mixture isn't all going through
the screen, or is sticking on the bottom, chances are
it's too wet. Take the mixture out of the strainer and
mix in some plain dry Meal Powder and try again. If
the mixture is going through easily, but isn't really
making granules, it might be a bit too dry. Take the
mixture out of the strainer and add a small amount of
water, mix well and try again.
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