(e) To fire, remove the safety pin, hold the barrel in one hand, and pull on the pull ring with the other hand.
0102. IMPROVISED STRING FUSE
a. Description.
This item consists of string, twine, or shoelaces that have been treated with either a mixture of potassium nitrate and granulated sugar or potassium chlorate and granulated sugar.
Improvised string fuse does not directly ignite any incendiaries listed in chapter 4 but is a primary initiator for all igniters listed in chapter 3 except: Potassium Permanganate —Glycerin (0206), Powdered Aluminum— Sulfur Pellets (0207), White Phosphorus (0209), and Subigniter For Thermite (0211).
Depending upon the length of the fuse, the user can be away from the immediate scene when an incendiary system is initiated.
b. Material and Equipment.
String, twine or shoelaces made of cotton or linen.
Potassium nitrate or potassium chlorate.
Granulated sugar.
Small cooking pot.
Spoon.
Heat source such as stove or hot plate.
Soap.
c. Preparation.
Wash string or shoelaces in hot soapy water; rinse in fresh water.
Dissolve one part potassium nitrate or potassium chlorate and one part granulated sugar in two parts hot water.
Soak string or shoelaces in the hot solution for at least five minutes.
Remove the string from hot solution and twist or braid three strands of string together.
Hang the fuse up to dry.
Check actual burning rate of the fuse by measuring the time it takes for a known length to burn.
d. Application.
This fuse does not have a waterproof coating and it must be tested by burning a measured length before actual use.
Cut the fuse long enough to allow a reasonable time delay in initiation of the incendiary system.
Insert one end of the fuse in a quantity of an igniter mixture so that the fuse end terminates near the center of the mixture. Be sure the fuse cord is anchored in the igniter mixture and cannot pull away. In the case of a solid igniter material such as Fire Fudge (0202), the improvised string fuse is securely wrapped around a piece of solid igniter material.
The fuse is initiated by lighting the free end of the fuse with a match.
This fuse does not burn when it is wet. Its use is not recommended where there is the possibility of the fuse getting wet.
0103. CONCENTRATED SULFURIC ACID (OIL OF VITRIOL)
a. Description.
This material is a heavy, corrosive, oily, and colorless liquid. Storage is recommended in a glass container with a glass lid or stopper. Commercially available sulfuric acid is approximately 93 percent concentration with a specific gravity of 1.835. This is commonly referred to as concentrated sulfuric acid.
Concentrated sulfuric acid chars wood, cotton, and vegetable fibers, usually without causing fire. The addition of water to concentrated sulfuric acid develops much heat which may be sufficient to cause a fire or an explosion. This depends upon the quantity of acid, quantity of water, and rate of addition of water. Caution: Always add concentrated sulfuric acid to water. Never add water to a concentrated acid.
Certain igniter materials can be reliably brought to flaming by the addition of concentrated sulfuric acid. This is brought about by the chemical reaction between the sulfuric acid and the igniter materials. The following igniters are initiated by concentrated sulfuric acid: Sugar-Chlorate (0201), Fire Fudge (0202), Sugar—Sodium Peroxide (0203), Aluminum Powder—Sodium Peroxide (0204), Match Head (0205), and Silver Nitrate—Magnesium Powder (0208).
The most important use for concentrated sulfuric acid as an initiator is in conjunction with delay mechanisms. The acid is held away from the igniter for a period of time by making use of the corrosive action of the acid to work its way through a barrier. If the delay mechanism is placed in a cold environment, the concentrated acid will remain fluid at extremely low temperatures. The following delay mechanisms are recommended for use with concentrated sulfuric acid: Gelatin Capsule (0402), Rubber Diaphragm (0403), Paper Diaphragm (0404), Tipping Delay—Filled tube (0408), Tipping Delay—Balancing Stick (0410), and Stretched Rubber Band (0411).
b. Material and Equipment. Concentrated sulfuric acid.
c. Preparation. None—If only battery-grade sulfuric acid is available (specific gravity 1.200), it must be concentrated before use to a specific gravity of 1.835. This is done by heating it in an enameled, heat-resistant glass or porcelain pot until dense, white fumes appear. Heat only in a well ventilated area. When dense, white fumes start to appear, remove the heat and allow acid to cool. Store the concentrated acid in a glass container.
d. Application.
General. Commercial sulfuric acid is available in 13 gallon carboys. Smaller quantities of this acid are available in chemical laboratory reagent storage containers. It is recommended that a small quantity of acid, about one pint, be secured and stored in a glass container until it is used.
Use with delay mechanisms. (a) Construction of specific delay mechanisms is described in chapter 5. Within the delay mechanism, there is a container filled with acid. The acid corrodes this container, is absorbed by the container material or is spilled from the container until it comes in contact with the igniter mixture.
(b) Carefully fill the container in the delay mechanism with concentrated sulfuric acid. This can be accomplished easily with a small glass funnel. A medicine dropper is used when the delay mechanism container is small. Caution: Concentrated sulfuric acid must be handled carefully because it is very corrosive. If it is splashed on clothing, skin or eyes, the affected area must be immediately flushed with water. This may not be always practical. It is recommended that eye protection be worn by the user when pouring concentrated sulfuric acid. Many types are available for this purpose. Rubber gloves can be worn to protect the hands. A small bottle of water can be carried to flush small areas of skin or clothing which may be contaminated with the acid.
Manual application. (a) Manual application of concentrated sulfuric acid for direct initiation of an igniter is not recommended when fuse cord is available. It is possible to employ this acid for direct initiation by quickly adding three or four drops to the igniter material. This can be accomplished with a medicine dropper. Keep hands and clothing clear of the igniter; ignition may take place almost instantly with addition of acid. Caution: Do not allow material such as sugar, wood, cotton or woolen fibers to fall into the boiling acid. A violent reaction could occur with splattering of acid.
(b) Since sulfuric acid has a unique freezing point related to acid concentration, the information shown below is useful when this acid is used with delay mechanisms in low temperature surroundings. Be sure of acid concentration by checking with a hydrometer.
Sulfuric acid concentration (%) Specific gravity Freezing point (° F.)
0 1.000 +32
10 1.074 +23
20 1.151 +5
30 1.229 —39
39 1.295 —97
40 1.306 —91
50 1.408 —31
60 1.510 —22
70 1.611 —40
75 1.686 —7
77 1.706 +12
80 1.726 +27
81 1.747 +39
89 1.818 +24
90 1.824 +13
92 1.830 —1
93 1.835 —29
0104. WATER
a. Description.
Water causes spontaneous initiation of certain igniter mixtures. This is caused by a chemical reaction of the igniter materials in the presence of water. The following igniters are initiated by water: Sugar—Sodium Peroxide (0203), Aluminum Powder—Sodium Peroxide (0204), and Silver Nitrate—Magnesium Powder (0208).
The most important use for water as an initiator is in conjunction with delay mechanisms. Since only a few igniter mixtures are initiated by water and it cannot be used at freezing temperatures, its use is limited. When tactics so dictate, water
can be reliably used with the following delay mechanisms: Gelatin Capsule (0402), Overflow (0407), Tipping Delay—Filled Tube (0408), Balancing Stick (0410), and Stretched Rubber Band (0411).
Note. Sulfuric acid of any concentration can be substituted for water in the initiation of water activated igniters. Water cannot be substituted for concentrated sulfuric acid.
b. Material and Equipment. Water.
c. Preparation. None.
d. Application.
Use with delay mechanisms. Construction of specific delay mechanisms is presented in chapter 5. Within the delay mechanism, there is a container filled with water. The water dissolves the container or is spilled from the container and comes in contact with igniter mixture, initiating the fire train.
Manual application. Fuse cord, when available, is recommended in preference to water as an initiator. Water is used for direct ignition of a specific igniter by adding drops as with a medicine dropper. Keep hands and clothing clear of the igniter; ignition may take place almost instantaneously with addition of water.
CHAPTER 3
IGNITERS
0201. SUGAR-CHLORATE
a. Description.
This item consists of a mixture of granulated sugar and potassium chlorate or sodium chlorate. It can be used to ignite all the incendiaries listed in chapter 4 except Thermite (0307). It may be used directly as an incendiary on readily flammable material such as rags, dry paper, dry hay, or in the combustible vapor above liquid fuels.
The igniter can be initiated by Fuse Cord (0101), Improvised String Fuse (0102), or Concentrated Sulfuric Acid (0103).
This simple sugar-chlorate mixture closely resembles granulated sugar and should not ordinarily arouse suspicion. It is an excellent igniter. Caution: This mixture is poisonous and must not be eaten.
b. Material and Equipment.
Granulated sugar (do not use powdered or confectioners sugar.)
Potassium chlorate or sodium chlorate (no coarser than granulated sugar).
Spoon (preferably nonmetallic).
Container with tight-fitting lid.
Rolling pin or round stick.
c. Preparation.
Using a clean, dry spoon, place granulated sugar in the container to one-quarter container volume. Wipe the spoon with a clean cloth.
If the potassium or sodium chlorate is lumpy, remove all lumps by crushing with a rolling pin. Using the spoon, add an equal quantity of chlorate to the container. Caution: If this mixture is carelessly handled with excessive bumping and scraping, It could be a fire hazard to the user. As a precaution, remove any mixture adhering to the lip or edge of the jar before tightening the lid.
Tighten the lid of the jar, turn the jar on its side and slowly roll until the two powders are completely mixed. The mixture is now ready for use. It may be stored for months in a tightly sealed container.
d. Application.
Carefully pour or spoon the mixture, in a single pile, on the incendiary. Prepare the mixture for ignition with Fuse Cord (0101) or Improvised String Fuse (0102) in the normal manner. The fuse cord should terminate near the center of the igniter mixture. Concentrated Sulfuric Acid (0103) can be used as an initiator, but is generally less convenient. Ignition takes place almost immediately on contact with the acid. Acid is recommended for use with specific delay mechanisms found in chapter 5.
If only battery-grade sulfuric acid is available, it must be concentrated before use to a specific gravity of 1.835 by heating it in an enameled, heat-resistant glass or porcelain pot until dense, white fumes start to appear. See paragraph 0103 for details.
When used to ignite flammable liquids, wrap a quantity of the mixture in a nonabsorbent material and suspend it inside the container near the open top. The container must remain open for easy ignition and combustion of the flammable liquid.
To minimize the hazard of premature ignition of flammable liquid vapors, allow at least two feet of fuse length to extend from the top edge of an open container of flammable liquid before lighting the fuse.
0202. FIRE FUDGE
a. Description.
This item consists of a mixture of sugar and potassium chlorate in a hot water solution which solidifies when cooled to room temperature. It can be used to ignite all the incendiaries listed in chapter 4 except Thermite (0307). It may be used directly as an incendiary on readily flammable material, such as rags, dry paper, dry hay, or in the combustible vapor above liquid fuels.
The igniter can be initiated by Fuse Cord (0101), Improvised String Fuse (0102), or Concentrated Sulfuric Acid (0103).
Fire fudge resembles a white sugar fudge having a smooth, hard surface. The advantage of this igniter material over Sugar-Chlorate (0201), is its moldability. The procedure for preparation must be followed closely to obtain a smooth, uniform material with a hard surface. Caution: This material is poisonous and must not be eaten.
b. Material and Equipment.
Granulated sugar (do not use powdered or confectioners sugar).
Potassium chlorate (no coarser than granulated sugar) .
Metallic, glass or enameled pan.
Measuring container (size of this container determines quantity of finished product).
Spoon (preferably nonmetallic).
Thermometer (to read in the range 200° F. to 250° F.)
Heat source.
c. Preparation.
Clean the pan by boiling some clean water in it for about five minutes. Discard the water, pour one measureful of clean water into the pan and warm it. Dry the measuring container and add one measureful of sugar. Stir the liquid until the sugar dissolves.
Boil the solution until a fairly thick syrup is obtained.
Remove the pan from the source of heat to a distance of at least six feet and shut off heat. Rapidly add two measurefuls of potassium chlorate. Stir gently for a minute to mix the syrup and powder, then pour or spoon the mixture into appropriate molds. If the mold is paper, it can usually be peeled off when the fire fudge cools and hardens. Pieces of cardboard or paper adhering to the igniter will not impair its use. Pyrex glass or ceramic molds can be used when a clear, smooth surface if desired. It is recommended that section thickness of molded fire fudge be at least one-half inch. If desired, molded fire fudge can be safely broken with the fingers.
This material is moderately hard immediately after cooling. It will become harder after 24 hours. When kept in a tightly sealed container, it will retain its effectiveness for months.
Caution: If this igniter material is carelessly handled with excessive bumping -or scraping, it could be a fire hazard to the user.
d. Application.
Place a piece of fire fudge on top of the incendiary. Minimum size should be about one inch square and one-half inch thick Prepare the fire fudge for ignition with Fuse Cord (0101) or Improvised String Fuse (0102) in the normal manner. Concentrated Sulfuric Acid (0103) can be used as an initiator but is generally less convenient. Acid is recommended for use with specific delay mechanisms found in chapter 5.
If only battery-grade sulfuric acid is available it must be concentrated before use to a specific gravity of 1.835 by heating it in an enameled, heat resistant glass or porcelain pot until dense, white fumes start to appear. See paragraph 0103 for details.
When used to ignite flammable liquids, wrap a quantity of the igniter mixture in a non-absorbent material and suspend it inside the container near the open top. The container must remain open for easy ignition and combustion of the flammable liquid.
To minimize the hazard of premature ignition of flammable liquid vapors, allow at least two feet of fuse length to extend from the top edge of an open container of flammable liquid before lighting the fuse.
0203. SUGAR-SODIUM PEROXIDE
a. Description.
This item consists of a mixture of sodium peroxide and granulated sugar. It can be used to ignite all the incendiaries listed in chapter 4 except Thermite (0307). It may be used directly as an incendiary on readily flammable material s
uch as rags, dry paper dry hay, or in the combustible vapor above liquid fuels.
The igniter can be initiated by Fuse Cord (0101), Improvised String Fuse (0102), Concentrated Sulfuric Acid (0103), or Water (0104). Caution: This mixture is unstable and can ignite at high humidity or when wet slightly by drops of water, perspiration, etc.
b. Material and Equipment.
Granulated sugar (do not use powdered or confectioners sugar).
Sodium peroxide (no coarser than granulated sugar).
Spoon.
Container with tight fitting lid for mixing and storage.
c. Preparation.
Using a clean, dry spoon, place granulated sugar in the container to one-quarter container volume.
Wipe the spoon with a clean, dry cloth, and add an equal amount of sodium peroxide to the dry mixing container. Tighten the lid on the sodium peroxide container, and remove it at least six feet from the working area.
Tighten the lid on the mixing container. Turn the container on its side and slowly roll until the two powders are completely mixed. The mixture is now ready for use.
A good practice is to keep the granulated sugar and sodium peroxide in separate airtight containers and mix just before use. Caution: Do not store this mixture longer than three days because decomposition may occur and cause spontaneous combustion. Be sure that the storage container is air-tight.
d. Application.
Carefully pour or spoon the mixture, in a single pile, on the incendiary. Prepare the mixture for ignition with Fuse Cord (0101) or Improvised String Fuse (0102) in the normal manner. The fuse cord should terminate near the center of the igniter mixture. Concentrated Sulfuric Acid (0103) and Water (0104) can be used as initiators, but are generally less convenient. Ignition takes place almost immediately on contact with the acid or water. These liquid initiators are convenient for use with specific delay mechanisms found in chapter 5.
U.S. Army Special Forces Guide to Unconventional Warfare Page 2