Gunpowder and Explosives

Why This Matters

Gunpowder is the first practical explosive available to a rebuilding civilization. Its primary value is not weapons but engineering: breaking rock for mining, quarrying stone for buildings, and clearing land for roads. Without explosives, tasks that take weeks of manual labor with hammer and chisel can be accomplished in minutes.

Extreme Danger

Gunpowder and explosives can kill or maim instantly. Every step in this article involves materials that can ignite, explode, or produce toxic fumes. Never work alone. Never rush. Never improvise safety shortcuts. Read this entire article before attempting anything.

Understanding Gunpowder

Gunpowder (black powder) is a mixture of three components:

• Potassium nitrate (saltpeter) — the oxidizer, provides oxygen for combustion
• Charcoal — the fuel, provides carbon
• Sulfur — lowers ignition temperature and increases burn rate

The classic ratio by weight is 75% saltpeter, 15% charcoal, 10% sulfur. This ratio has been refined over centuries and should not be modified.

Component	Percentage	Role	Source
Potassium nitrate	75%	Oxidizer	Niter beds, manure soil
Charcoal	15%	Fuel	Willow, alder wood
Sulfur	10%	Ignition aid	Volcanic deposits, pyrite

Extracting Saltpeter (Potassium Nitrate)

Saltpeter is the hardest ingredient to obtain and the most critical. It forms naturally when nitrogen-rich organic matter decomposes in contact with alkaline earth.

Building Niter Beds

A niter bed is essentially a controlled composting operation optimized for nitrate production.

1. Select a sheltered location — a roofed area open on the sides, protected from rain but with good airflow
2. Build a bed 1 meter deep, 2 meters wide, any practical length
3. Layer materials: mix animal manure (horse, cattle, poultry), wood ash, straw, and ordinary soil in roughly equal volumes
4. Add urine — human or animal urine is the richest nitrogen source; collect and pour over the bed weekly
5. Turn the pile every 2-3 weeks to aerate
6. Keep moist but not wet — the consistency of a wrung-out sponge
7. Wait 6-12 months — bacteria convert ammonia to nitrites, then nitrates

Speed It Up

Adding old mortar, plaster, or limestone rubble to the bed provides calcium that helps fix nitrates in the soil. Beds in warm climates produce faster. In tropical regions, expect usable niter in 4-6 months.

Leaching Saltpeter from Soil

Whether from niter beds or naturally nitrate-rich soil (found in caves, under old barns, or near animal pens):

1. Collect the soil and break up any clumps
2. Build a leaching trough: a V-shaped wooden trough or a barrel with a spigot near the bottom, lined with straw as a filter
3. Pack the soil into the trough, not too tight
4. Pour warm water slowly over the soil — use about 4 liters of water per kilogram of soil
5. Collect the brown liquid (lye) that drains out
6. Test concentration: dip a feather in the liquid — if the barbs curl and dissolve, it contains significant nitrate

Do Not Confuse

This leaching process is similar to making potash lye for soap. The liquids look identical. Label your containers clearly. Mixing up saltpeter solution with lye solution will ruin both products.

Purifying by Recrystallization

Raw leachate contains many dissolved salts. You need pure potassium nitrate.

1. Boil the leachate in a large iron or copper pot, reducing volume by about 75%
2. Add wood ash water (potash solution) to the hot concentrate — this converts calcium nitrate and sodium nitrate to potassium nitrate
3. Skim off scum and filter through cloth while hot
4. Pour into wide, shallow wooden trays
5. Cool slowly — potassium nitrate crystallizes as long, needle-like crystals
6. Scrape out crystals, drain, and set aside the remaining liquid
7. Redissolve crystals in minimum hot water and recrystallize a second time for higher purity
8. Dry crystals thoroughly in shade — never over open flame

Good saltpeter should be white, needle-shaped crystals that taste cool and slightly salty. When placed on hot coals, pure saltpeter burns with a bright violet-tinged flame and leaves minimal residue.

Preparing Charcoal

Not all charcoal is equal for gunpowder. You want the lightest, most porous charcoal possible.

Wood Type	Quality	Notes
Willow	Excellent	Traditional choice, very light
Alder	Excellent	Fine grain, easy to powder
Grapevine	Very good	Burns fast, hot
Hazel	Good	Widely available
Pine/fir	Poor	Too much reite, inconsistent
Hardwoods (oak)	Poor	Too dense, slow burning

Making Gunpowder-Grade Charcoal

1. Cut wood into uniform pieces, 2-3 cm diameter, remove all bark
2. Char in a sealed container (retort method): pack pieces tightly in a metal can with a small vent hole
3. Heat the container in a fire until smoke stops coming from the vent — this takes 1-2 hours
4. Seal the vent and let cool completely before opening
5. Test: good charcoal should be jet black throughout, snap cleanly, feel nearly weightless, and leave a black mark when rubbed on a surface

Grind Immediately

Charcoal absorbs moisture from the air. Grind it to fine powder within hours of making it, and store the powder in airtight containers. The finer the powder, the better the gunpowder.

Sourcing Sulfur

Volcanic and Geothermal Sources

If you are near volcanic terrain, sulfur deposits appear as bright yellow crusts around hot springs, fumaroles, and volcanic vents. Collect the yellow crystite carefully — volcanic gases are toxic.

Sulfur from Pyrite (Iron Sulfide)

Pyrite (“fool’s gold”) is common worldwide. To extract sulfur:

1. Crush pyrite to gravel-sized pieces
2. Roast in a clay retort — a sealed pot with a downward-angled tube leading to a collection vessel
3. Heat strongly for several hours — sulfur vapor travels through the tube and condenses as a yellow liquid/solid in the collector
4. Purify: melt collected sulfur at low heat (just above 115 C), filter through cloth, and cast into molds

Toxic Fumes

Roasting pyrite produces sulfur dioxide gas, which is highly toxic. Always work outdoors with wind at your back. Never breathe the fumes. Even brief exposure causes severe lung irritation.

Sulfur Purification

For best results, purify sulfur by sublimation:

1. Place crude sulfur in an iron pot
2. Invert a larger pot over it as a “dome”
3. Heat gently — sulfur vapor rises and condenses on the cool dome as fine yellow powder (“flowers of sulfur”)
4. Scrape off the fine powder — this is the purest form, ideal for gunpowder

Mixing Gunpowder

Critical Safety Rules for Mixing

• NEVER mix dry ingredients near any flame, spark, or heat source
• NEVER use metal tools that could create sparks — use wooden or bone implements
• NEVER mix more than 500 grams at one time
• ALWAYS work outdoors, away from buildings
• ALWAYS have water buckets within arm’s reach
• Wear no synthetic clothing — static electricity can ignite powder

The Wet Mixing Method (Safest)

1. Weigh ingredients precisely:

   • 75 grams potassium nitrate
   • 15 grams charcoal powder
   • 10 grams sulfur powder (per 100 gram batch)

2. Grind each ingredient separately to the finest possible powder using a mortar and pestle. Each should feel smooth, not gritty, when rubbed between fingers.

3. Dissolve saltpeter in minimum hot water (about 30 ml per 75 grams)

4. Add charcoal and sulfur powders to the saltpeter solution

5. Mix thoroughly with a wooden spatula for at least 15 minutes — the mixture should be a uniform dark gray paste with no visible streaks or lumps

6. Spread the paste in a thin layer on wooden boards

7. Dry in shade — never in direct sunlight or near heat. Stir occasionally to prevent crust formation. This takes 12-24 hours depending on humidity.

Corning (Granulation)

Loose powder (“serpentine”) is weak and inconsistent. Corning dramatically improves performance:

1. While the powder paste is still slightly damp (like wet sand), press it through a coarse sieve or screen (2-3 mm mesh)
2. The granules that form should be uniform in size
3. Dry the granules completely — they should feel hard and rattle when shaken
4. Sieve again to separate dust (too fine) from grains (useful) from chunks (regrind)
5. Polish: tumble dried granules gently in a wooden container to round off sharp edges

Why Corning Matters

Corned powder burns 3-4 times more powerfully than the same weight of loose powder. The air spaces between granules allow flame to penetrate the entire charge simultaneously. Serpentine powder often just fizzles.

Testing Your Powder

Before trusting your gunpowder for any application, test it:

1. Trail test: pour a thin line of powder 30 cm long on a flat surface outdoors. Light one end. Good powder burns the entire trail in under 2 seconds with a bright flash and minimal smoke residue.
2. Pile test: place a small pile (5 grams) on a flat rock. Light it. Good powder should flash instantly, leaving only a light white residue. If black residue remains, charcoal quality or the ratio is off.
3. Consistency test: repeat 3-4 times. Results should be identical each time.

Result	Diagnosis	Fix
Slow, sputtering burn	Saltpeter impure or too little	Re-purify saltpeter, check ratio
Bright flash but much residue	Too much charcoal	Reduce charcoal, reweigh
Won’t ignite	Moisture contamination	Dry completely, regrind
Burns unevenly	Poor mixing	Remix with wet method
Weak flash, little force	Serpentine not corned	Corn the powder

Blasting for Mining and Quarrying

The primary civilizational use of gunpowder is breaking rock — for mining ore, quarrying building stone, and clearing paths for roads.

Drilling Blast Holes

1. Mark your drill point based on the rock face and desired fracture line
2. Use a star drill (chisel-pointed iron bar) and hammer. Rotate the drill 1/8 turn between each hammer strike.
3. Drill holes 30-60 cm deep, 2-3 cm diameter
4. Clear dust by blowing through a hollow reed or pouring water periodically
5. Dry the hole completely before loading — moisture ruins the charge

Loading and Tamping

Tamping Danger

NEVER use a metal tamping rod. Use only wooden or copper rods. A metal rod striking rock can create a spark that detonates the charge in your hands.

1. Pour gunpowder into the hole — typically 50-200 grams depending on rock hardness and hole depth
2. Insert the fuse (see below), ensuring it reaches the powder
3. Tamp gently with a wooden rod — press the powder down firmly but without pounding
4. Add stemming material: pack the remaining hole with dry clay, sand, or drill cuttings above the charge
5. Tamp the stemming firmly — this contains the blast force and directs it into the rock

Blast Sequence

1. Clear the area — minimum 50 meters for small charges, 100+ meters for large ones
2. Post sentries at all approach paths
3. Establish signals: three horn blasts = about to light, one long blast = all clear
4. Light the fuse and retreat immediately to cover
5. Wait at least 5 minutes after the blast before approaching — misfires can delay-detonate
6. Approach cautiously from upwind, checking for undetonated charges or unstable rock

Making Fuses

Slow Match

Slow match burns at about 30 cm per hour — too slow for blasting but useful for carrying fire.

1. Soak cotton or hemp rope (10 mm diameter) in a strong saltpeter solution (1 part saltpeter to 4 parts water)
2. Dry thoroughly
3. Test: light one end — it should glow and smolder steadily without flame

Quick Match

Quick match burns at roughly 30 cm per second.

1. Coat cotton string with a paste of fine gunpowder mixed with gum arabic or flour paste
2. Dry completely
3. Enclose in a loose paper tube — the confinement dramatically increases burn speed

Safety Fuse

A proper safety fuse burns at a known, consistent rate (ideally 1 cm per second):

1. Lay a thin, consistent trail of fine gunpowder along a groove in a wooden board
2. Press cotton yarn into the powder
3. Wrap tightly with cotton thread, then coat with melted wax or pitch
4. Test a measured length to determine exact burn rate
5. Calculate fuse length based on the time needed to reach safe distance at a run

Always Cut Long

If your fuse burns at 1 cm/second and you need 30 seconds to reach cover, cut at least 50 cm of fuse. Extra time is never wasted. Insufficient time is fatal.

Storage and Safety

Storage Requirements

Requirement	Reason
Cool and dry	Moisture ruins powder; heat can cause spontaneous ignition
Away from all buildings	Accidental detonation destroys structures
In wooden or earthenware containers	Metal containers become shrapnel
Components stored separately	Mixed powder is vastly more dangerous than components
Small quantities only	Never store more than you need for the week
Clearly labeled and locked	Prevent unauthorized access

Handling Rules

• Ground yourself before handling — touch bare earth to discharge static
• Wear cotton clothing only — wool and leather create static
• No smoking, no lanterns, no open flames within 20 meters
• Work in daylight only — never handle powder by firelight or candlelight
• Clean up all spills immediately — even a thin dust layer can flash-ignite
• Wash hands and tools after handling

The Cardinal Rule

Treat every container of gunpowder as if it will explode at any moment. Keep your face and body away from the opening of any container. Never look into a loaded blast hole. Never test a charge “just to see what happens.”

Common Problems and Solutions

Problem	Cause	Solution
Powder won’t ignite	Moisture absorption	Re-dry, regrind, recorn
Weak explosion	Impure saltpeter	Re-purify by double recrystallization
Charge blows out of hole	Insufficient stemming	Pack stemming more firmly, use clay
Misfire (no detonation)	Fuse extinguished	Wait 30 minutes, then carefully re-fuse
Rock shatters instead of fracturing	Too much powder	Reduce charge, drill more holes
Powder cakes into solid block	Stored in humid conditions	Break up, regrind, dry thoroughly

What’s Next

With controlled explosives, you can extract metal ores from deep rock faces for Metalworking and blast paths through difficult terrain for Roads and Transport. The saltpeter extraction skills also support Fertilizer production, since potassium nitrate is an excellent plant nutrient.

Gunpowder and Explosives -- At a Glance

Ratio: 75% potassium nitrate, 15% charcoal, 10% sulfur Saltpeter source: Niter beds (manure + ash + soil, 6-12 months), or cave/barn soil leaching Best charcoal: Willow, alder, or grapevine, charred in sealed container Sulfur sources: Volcanic deposits, pyrite roasting, sublimation purification Mixing: ALWAYS wet method, wooden tools only, outdoors, small batches Corning: Press damp paste through 2-3 mm sieve, dry completely Blasting: 30-60 cm holes, wooden tamping rod, clay stemming, 50 m minimum clearance Fuse burn rates: Slow match ~30 cm/hr, safety fuse ~1 cm/sec, quick match ~30 cm/sec Storage: Cool, dry, wooden containers, components separate, small quantities The rule: If in doubt, don’t. No amount of blasted rock is worth a life.