Powder

H. M. Royal Artillery

"Artillery lends dignity to what would otherwise be a vulgar brawl"

Black Powder

Gunpowder, which we know today as black powder, was the first chemical explosive and, until the mid-19th century, was the only one known. While the precise amount of each chemical has varied widely over the years, today black powder is a mixture of 75 percent potassium nitrate (saltpeter), 15 percent charcoal and 10 percent sulfur. In this mixture, charcoal is the fuel and potassium nitrate is the oxidizer. While sulfer is also a fuel, it's the main purpose is to lower the temperature required to ignite the mixture, thereby increasing the rate of combustion. Because of its burning properties, the amount of heat and volume of gas that it generates, gunpowder has been widely used as a pyrotechnic composition in fireworks and also as a propellant in firearms. Formulations used for blasting rock in mining and quarrying are known as blasting powder.

While there is no hard and fast evidence, many scholars believe that gunpowder was invented around the mid 9th century in China by Taoist alchemists searching for an elixir of immortality. This accidental discovery changed the world forever. The earliest record of a written formula for gunpowder appears in an 11th century Song Dynasty text. The discovery of this mixture led first to the invention of fireworks and thereafter to the earliest gunpowder weapons. Rockets, cannon, crude firearms and grenades were all used by the Chinese in their wars against the Mongols. Hand cannons (handgonnes) that date from the early 1200's have been found in China.

In the centuries following the Chinese discovery, gunpowder, and it's associated weapons, began appearing in the Muslim world, India and Europe. The earliest Western accounts of gunpowder appear in texts written in 1248 by English philosopher Roger Bacon in which he describes a recipe for gunpowder and recognized its military use. European handgonnes first appeared in the early 1300's and by 1350 early forms of cannons were commonplace in the English and French militaries.

As weapons became more sophisticated, very large cannon eventually replaced the trebuchet as the siege weapon of choice. One of these monster guns, named Mons Meg, was built in 1449 and is still on display at Edinburgh Castle in Scotland. The gun is 15 feet long, weighs 15,366 pounds and could fire a 20 inch diameter, 400 pound projectile, two miles. While it saw action against the English at the siege of Norham Castle in 1497, there were serious problems associated with this huge gun. Due to the tremendous heat generated by the powder charge required, it could only be fired 8-10 times a day. In addition, its great weight meant that it could be moved at a rate of only three miles a day. Because of these issues, it was retired in the 1540's, and then used only on ceremonial occasions. Cannon were quickly scaled down to more manageable sizes.

Mons Meg

Originally, gunpowder was made by grinding the three dry chemicals together for as long as 24 hours. As you can imagine, this process was rather dangerous and manufacturing accidents were not uncommon. In Europe, this mixture was called Serpentine and it was a fine, flour or dust like powder that burned slowly and gave low pressures. Loading guns with this powder was a real art because if it was either too compressed or too loose, it wouldn't burn correctly. In addition, vibration during transportation could cause the components to separate again, requiring remixing in the field.

A major advance in the manufacturing of gunpowder took place in the late 14th century when European powder makers first began adding liquid during grinding. This improved mixing, reduced dust, and, more importantly, the risk of explosion. They would then shape the resulting paste of dampened gunpowder, known as mill cake, into corns, or grains, to dry. Not only did corned powder keep better because of its reduced surface area, gunners also found that it was more powerful and easier to load into guns.

This wet mixed, corned gunpowder was from 30 to 300 percent more powerful than the earlier dry mixed powder. An example is cited where 34 pounds of dry mix Serpentine was needed to shoot a 47 pound ball a given distance, but only 18 pounds of wet mix corned powder was needed for the same shot. Before long, powder makers standardized the process by forcing mill cake through sieves instead of corning powder by hand. The optimum size of the grain depended on its use, larger grains for cannon and finer for small arms. This still remains true today.

Originally, cannon were muzzle-loaded with loose powder using a long-handled ladle but in the 1600's, cloth powder bags came into common use. This made loading much faster, safer and easier. Corned powder also had the advantage of low moisture absorption. This was important because as powder absorbs moisture from the air, it becomes much less powerful. If it gets too damp, it won't burn at all and thus becomes useless.

The art of making gun powder, along with that of casting cannon and shot, were closely held secrets by skilled military tradesmen. They formed guilds which collected dues, trained and tested apprentices, and gave pensions.

Today, black powder is classified as a low explosive. Low explosives deflagrate at subsonic speeds, they do not actually explode. 'Deflagrate' is just a fancy word which means 'fast-burning'. In contrast, high explosives detonate, producing a supersonic shock wave. Even though it's a low explosive, black powder can be shipped as a flammable solid by authorized dealers via ground transportation.

Ignition of black powder brings about a rapid reaction in which energy is generated in the form of heat and a large amount of gas. The heating causes the gases to expand rapidly, producing an explosive force, especially if confined. The faster the reaction, the more powerful the force. If this process is fully enclosed, we have a bomb and when the internal pressure exceeds the container's ability to withstand it, we have an explosion.

However, if the container has an opening, such as the open muzzle of a gun barrel, the expanding gases can be used to propel a projectile along its length. The length of the barrel allows the process to sustain a major portion of the initial pressure, as the inertia of the projectile is overcome. The projectile continues to accelerate until it leaves the barrel, at which time, the effects of air resistance, and to a smaller effect, gravity, cause it to decelerate at predictable rates.

The name "Black Powder" is relatively modern. It comes from the fact that the first smokeless powder, developed in the late 1800's, was a light gray color compared to the dark black of the propellant it would largely replace. As stated earlier, prior to that time black powder was simply called gunpowder.

Currently, there are seven grades of sporting ('Type G') black powder that are commonly used for muzzleloading weapons.
Grade Granule Size (in mm)
Cannon 4.76 - 1.68

1Fg 1.68 - 1.19

1.5Fg .1.45 - 0.89

2Fg 1.19 - 0.59

3Fg 0.84 - 0.29

4Fg 0.42 - 0.15

0BFg (Null B) 0.23 - 0.19

1.5Fg and Null B are only made by the Schuetzen Powder Company in their Swiss brand black powder. At one time Goex made a 5Fg (.149mm) grade but they stopped making it years ago.

The "F" designation is the screen size used in manufacture and the resultant grain size (coarseness). The smaller the size of the granule, the faster the powder burns and the higher the pressure that is produced in the barrel. Because of this, the different granule sizes have specific uses.

Cannon Grade is a special granulation for optimum performance in cannons with a bore diameter of 1.75 inches and larger.

Fg (referred to as 'one F') is used in cannon with a bore diameter of 1.75 inches and under, .68 caliber and larger long guns and 12-bore and larger shotguns.

1.5Fg (one & a half F) can be used for anything over .50 caliber except for large bore cannons. It's also used in black powder cartridge loads.

FFg ('two F') is used in long guns and pistols from .50 to .68 caliber and shotguns under 12-bore

FFFg ('three F') is used in long guns and pistols from .30 to .50 caliber

FFFFg ('four F') is used for priming flintlocks and cannon only.

0BFg ('Null B') is used for priming flintlocks only. As the fastest priming powder in the world, some shooters like it because with its smaller grain size, it ignites a little easier and burns a bit faster. In a flintlock, this can mean less delay between squeezing the trigger and the main charge going off. Some feel that this shortened delay can help improve accuracy.

WARNING!!! - Four F and Null B are used to prime flintlocks and cannon ONLY. NEVER use either one as the main charge in a firearm. Doing so will cause dangerously excessive pressure in the barrel which can result in the destruction of the firearm and serious injury or death to the shooter and possibly bystanders.

We often get asked "What does the letter "F" stand for? The answer is that it stands for "Fine" and goes back to the days when grain size was designated as F or C for "fine" or "coarse" grains. As you can see from the chart above, the more the number of times the letter F appears the smaller the grain size.

Today, sporting black powder comes packaged in one pound containers and can be purchased locally or on-line in quantities not to exceed 50 pounds per person. The purchase of any quantity over 50 pounds or bulk packed powder requires a Federal explosives permit as well as a BATFE approved powder magazine for storage. (see the 'Legal Stuff' page).

During a typical show season, H. M. Royal Artillery will usually burn through 90 pounds of black powder. 60 pounds of that is used during the seven weeks of the Florida Renaissance Festival to open and close the show and conduct our live fire cannon and mortar demonstration. Because we use so much powder during a show season, we buy it in 50 pound lots. Purchased in single cans, black powder can cost from $25 to $52.00 per pound depending on type, brand and supplier. Fortunately, since we buy black powder in quantity, we have found sources where we are able to get it for significantly less.

As a propellant, black powder is horribly inefficient because only about 45 to 50 percent of its mass turns into gas. The rest is solid residue that is forced out the muzzle as white smoke or left in the bore as corrosive fouling crud. This fouling in the barrel readily absorbs water vapor from the air which can rapidly result in the formation of rust. It's very important to thoroughly clean a weapon as soon as possible after firing.

A second type of black powder which the reader has often been exposed to, probably without knowing it, is fireworks ('Type A') powder. This powder has been a vital part of fireworks celebrations for over a thousand years. It provides the lift and bursting charge in aerial displays and is used, in one way or another, in almost every other pyrotechnic device and component. In fact, without black powder, there wouldn't be fireworks.

Fireworks powder is the exact same mixture of 75 percent potassium nitrate, 15 percent charcoal and 10 percent sulfur that is found in sporting powder. The difference in the two types of powder comes from how they are processed after the base chemicals are combined.

Some reference sources refer to fireworks type powder as 'blasting' powder but this isn't completely accurate. While FA powder is used for blasting, true blasting powder is 'Type B' which has a different chemical composition (see below).

Today there are ten different granulations of fireworks powder in common use. These are:
Grade                   Granule Size (in mm)
FA 5.66 - 4.00
2FA 4.76 - 1.68
3FA 2.00 - 1.19
4FA    1.68 - .840
5FA .840 - .297
6FA    .595 - .297
7FA .420 - .149
Meal D <.420 to dust
Meal F    <.149 to dust
Meal XF    <.105 to dust

Several grades of fireworks powder match up with those of sporting powder:

2FA = Cannon Grade
4FA = 1Fg
5FA = 3Fg
7FA = 4Fg

Notice that there is no fireworks powder equivalent for 1.5Fg, 2Fg or Null B sporting powder and no sporting powder equivalent for 6FA or Meal fireworks powder. As you might imagine, discussions comparing the two types of powder can easily become confusing.

The granules of fireworks powder have very rough shapes like freshly crushed stone while the granules of sporting powder are tumbled with graphite resulting in them being polished to a much more uniform shape like well worn river rocks. Fireworks powder is less dense due to the more irregular shapes occupying more volume for a given weight of powder. Also, because of the rough shapes, fireworks powder has a larger surface area for a given granule size. The graphite coating on sporting grade black powder also slows the burn rate very minutely. Fireworks powder most often does not have this coating.

The rough shape, lower density, greater surface area and the usual lack of graphite coating results in fireworks powder having a very slightly faster burn rate than sporting powder. As we have shown, several grades of fireworks powder can be substituted for sporting powder in muzzleloading weapons. However, since the faster burn rate produces somewhat higher barrel pressures, care must always be taken to carefully measure the powder to insure that the maximum allowable charge for the weapon is never exceeded.

WARNING: Like 4Fg and Null B sporting powder, 6FA and 7FA should NEVER be used in a weapon except for priming flintlocks or cannon touch holes. Using either of these grades of powder as the main charge will cause dangerously excessive pressure in the barrel which can result in the destruction of the firearm and serious injury or death to the shooter and possibly to bystanders. Meal D, Meal F and Meal XF are used almost exclusively in the manufacturing of fireworks. While these grades aren't usually available to the BP shooting community, if they are obtained they should ONLY be used for priming. Using as a main charge could likely cause a catastrophic failure of the weapon.

Powder charges for muzzleloading weapons with less than a 1 inch bore are generally referred to in 'grains' as in "the pistol was loaded with a 60 grain charge." 437.5 grains equals one ounce and 7000 grains equals one pound. Due to the uniformity of size and relatively smooth granule shapes, sporting (Fg) black powder lends itself to reasonably accurate measurement by volume. Some sources will tell you that fireworks powder usually must be weighed in order to obtain equally accurate volume measurement. However, we conducted experiments using a commercial powder measure and a digital scale that measures grains and have proved that this is not the case.

FA fireworks powder usually comes in bulk packs of 25 pounds. Just like bulk packed Fg sporting powder, to purchase it and/or have it shipped to you, a Federal explosives user permit or manufacturing license is mandatory along with an approved powder magazine. Normally, the license and magazine requirement makes bulk FA fireworks powder basically useless to us because the process to obtain the license and magazine is lengthy, complicated and expensive. Fortunately however, we have been able to locate a few sources for FA powder that has been repacked into 1 lb cans. This allows it to be sold and shipped just like Fg powder. Since it costs significantly less than Fg sporting powder we have changed over to using FA powder almost exclusively which has resulted in a considerable cost savings for us.

A third type of black powder is Blasting ('Type B') Powder. It differs from sporting and fireworks powders in that its formula uses the cheaper sodium nitrate instead of potassium nitrate. While Type B is usually made in standard proportions of 70% nitrate, 14% charcoal, and 16% sulfur and may be as low as 40% nitrate, 30% charcoal, and 30% sulfur. Blasting powder comes in four grades, 1FB through 4FB and is used for dimensional stone blasting where minimal shattering effect is required. Years ago blasting powders were used extensively in the coal mining industry. Today, in the United States, it is typically used for precision stone cutting of marble, granite, and slate. Blasting powder is more powerful than sporting or fireworks powder and should NEVER be used in muzzleloading weapons or fireworks. Like fireworks powder, Type B blasting powder is bulk packaged and its purchase, storage and use requires a Federal explosives license and approved magazine for storage.

Unfortunately there are many beliefs about black powder that are dangerously wrong. One of these myths, that is quite common, is that it's not possible to overload a modern black powder weapon. We've actually had people tell us with absolute certanity that a weapon can be filled all the way to the muzzle with black powder and then safely fired. They claim that any excess, unburned powder will just get pushed out of the barrel.

The truth is, that much powder would act as a barrel obstruction and would, in effect, turn the weapon into a pipe bomb. Actually firing a weapon in this condition would end up with very tragic results for the shooter as well as any bystanders. Cannons and small arms all have maximum safe loads which should never be exceeded. This is true even when firing blank shots as we normally do. Actual live firing of projectiles requires even more care since the barrel pressures developed are significantly higher than those of a blank shot.

A second myth about black powder is that the more powder you use, the bigger the bang you will get. Again, this is completely false. Belief in this myth, and putting it into practice, could result in dangerous overloading of the weapon by exceeding the maximum safe charge.

While black powder is very safe if handled and stored properly, certain precautions should always be followed. It should always be stored in a cool, dry place and handled with care to avoid impact, friction, heat, sparks and open flame. Containers should always be kept tightly closed when not in use and nearby smoking prohibited. Remember that black powder is extremely flammable and explosive! Careless storage or handling can result in destruction of property and serious bodily injury or death!

Occasionally, we are asked if modern black powder substitutes such as Pyrodex^®, Triple-Seven^®, Pinnacle^® and others can be used instead of real black powder. While these powders are excellent for target shooting and hunting with modern inline muzzleloading rifles, they are not at all suitable for reenacting. All of these powders have a reduced sensitivity to ignition which makes their use very problematic in our small arms by greatly increasing the chance of a misfire. Flintlocks need very sensitive, finely granulated powder in the flash pan and the spark from the flint isn’t usually hot enough to set off BP substitutes. Even our percussion guns would require special magnum percussion caps instead of the standard #11 caps that we normally use. Due to barrel pressure concerns, BP substitutes can’t be used at all in our cannons. Last, but just as impoetant, is the fact that they produce very little smoke when fired and the heavy white smoke from real black powder is an effect that both we and our audience want.

Finally, a word of warning: NEVER, EVER, FOR ANY REASON, use modern smokeless gunpowder in a muzzleloading black powder weapon.

Even with correct loads, black powder barrel pressures can be up to 27,000 psi. However, modern smokeless powder is about three times as powerful as black powder and can create barrel pressures from 40,000 psi up to 65,000 psi. Muzzleloaders ARE NOT designed for that kind of pressure.

The use of modern smokeless gunpowder in a muzzleloading black powder weapon will result in barrel failure and serious injury or death.

This was a replica of a muzzleloading Civil War Enfield rifle that was overloaded with black powder.
The shooter was seriously injured.

Using smokeless gunpowder, in ANY amount, will have the same results.

Catastrophically burst barrel of a replica muzzleloading pistol. During testing, the barrel was loaded with
modern smokeless powder instead of black powder. Fortunately, no one was hurt.

Always get proper training in the safe handling and use of black powder and the weapons that use it.

H. M. Royal Artillery can and will help you with this training. See our 'Contact Us' page.

NOTE: On September 28, 2021, the Hodgdon Powder Company, the owners of Goex, announced that they had permanently ceased production of black powder. Founded in 1802, Goex was the last black powder manufacturer in the U.S. What the long term effect this will have on the black powder shooting community remains to be seen. At one time there were 9 brands of black powder available. With the demise of Goex there are now only three brands from two European companies. While both of those companies produce excellent black powder, all of us are really hoping that Goex will be sold to a new owner and eventually reopened.