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Artillery projectiles, fuzes and propellants
Artillery Projectiles, Fuzes and Propellants Royal Canadian Artillery School Table of Contents Introduction Main Topic Projectiles Propellants Conclusion Sources
The weapon of the Artillery is often thought to be the cannon or howitzer. The
weapon of the artillery is the projectile. I will give an overview of middle aged to modern
era projectiles, fuzes and propellants. The origins of the artillery based weapons can be
dated back 61,000 years to the age of the bow and arrow, the first propelled weapon
system used as hunting and killing tool (Britanica, Bow and Arrow). I will be focusing on
the more recent aspects of Artillery weapons systems from 1132 in the province of Jujian
in China to modern era weapon systems deployed in Canada.
The projectile of artillery weapons has evolved from the hollowed out balls to the
common shell we see today. The first hollowed out balls were filled with gun powder and
shrapnel. The gun powder would be ignited and the carrier ball would disperse shrapnel
fragments (Hamilton, 13). These shells were ignited by a timed fuze (wick) and impact
mechanisms. As we move into the 16th century we see the evolution of the projectile into
a cast iron hollowed ball. Earliest dated cast iron hollow ball is 1580 as reported by
Spiegel International. These iron balls were still filled with gun powder and ignited by an
external fuze with no precise timing. With the a little innovation in the 18th century it was
realized that windage was used to ignite the fuze inside the barrel. Windage refers to the
propelling charge, when ignited would travel through the barrel causing the fuze in the
projectile catch. This eliminated the need to ignite the fuze before loading it (Hogg). In
the mid 19th century the common shaped artillery shell was adopted and is in use today.
This was normally made of cast iron but other metals and including glass was tested
(Hogg, 164). During this time there were several attempts to increase the projectiles
velocity and accuracy in firing. The key thing that had to happen was to reduce windage
created inside the bore. The first attempt was by the use of a sabot. This device was
smaller than the bore that provided the centering of the projectile in the bore and increase
initial start pressure forcing the round out. The next advance in providing accurate firing
and greater start pressure was introduced with the invention of rifling the bore. This
rifling was applied to artillery weapons by Armstrong, Whitworth and Lancaster. They
used the rifling principles which were invented by Jaspard Zoller at the end of the 15th
century (Hogg). This provided greater accuracy in the delivery of the projectile that put a
spin on an elongated projectile. After trial and error, from lead coated projectiles and
studded projectiles a copper band around the projectile was adopted. This copper band
when put under stress would form to the rifling of the bore. This provided rotation, initial
start pressure and it seated the round centered in the bore (Hogg, 165). The shape of the
projectile is elongated and is describes by 7 parts: Body, shoulders, ogive, base, base
plug, rotating band (driving band) and bourlette. Reference Annex A.
Fuzes as discussed earlier started off as igniting a combustible material that had a
specific burn time. This was not the most precise method as it required time measurement
and recording to have precise delivery (Hogg). As stated earlier, windage enabled the
ignition of the fuze by using the propelling charge flash. The earliest account for
percussion fuzes were in 1650, this used a flint to create spark which would ignite the
gun powder contained inside the carrier shell (Hogg). There were some attempts to create
a better fuze with examples such as mercury fulimate in 1800 which was highly explosive
and dangerous to handle; to copper percussion caps used in1818. It wasn’t until 1846
when a wooden fuze was created. 6 inches long and used shear wire to hold blocks
between the fuze magazine and a burning match. The match was ignited by propellant
flash and the shear wire broke on impact (Hogg, 203).With the introduction to rifled
breech loading guns it introduced percussion nose fitted fuzes. The fuzes were detonated
upon impact of a surface. This caused a chain reaction to occur causing the fuze to
detonate the contents inside of the carrier shell. Fuzes used in the modern era have many
functions all of which apply the same principle of carrying a chain reaction to occur
which detonates a projectile or causes one to function. Some of these functions are: Point
Detonating (PD), Delay, time and proximity. These fuzes can be one of two types
disruptive or igniferous. An igniferous fuze produces a flash or spit of flame that is used
to expel the contents of the projectile. This fuze can be used for smoke and illumination.
Disruptive fuzes produce a detonation which detonates the projectile filling (RCAS). The
following picture is a disruptive fuze. This is the M577 which has two settings, delay and
super quick also know as PD. As seen in annex b the fuze has the M125A1 booster. This
booster provides a 60m delay arming in front of the howitzer along with providing an
amplified shock wave to cause the projectile to detonate. The booster cap functions from
the obturation (turning of the projectile). The centripetal force of the projectile causes
booster cap to allow the primer to detonate. Another example of a disruptive fuze is the
M739A1 fuze reference Annex C. A few examples of igniferous fuzes are the M582A1
and the C32A1 (annex d). The M582A1 fuze is used in a time function. This function
allows the delivery of the projectiles contents at the time required. The fuze is set
manually and it displays the fuze setting in an analog view. For example this fuze can
expel an illumination, smoke or cause a high explosive round to detonate at a specific
time. The C32A1 fuze can be used as a time, delay or proximity functions. The proximity
setting will arm after a set value indicated by the command post and it will activate its
sensors. Once the sensor detects an object it will cause the projectile to explode. This
fuze also has the time function just as the M582A1 and the delay function of the
M739A1. The advancement in fuzes has enabled artillery men to deliver the projectile
and have it function where they want it more effectively. The proximity, time, PD and
delay fuzes are commonly used in NATO Forces. The modern era fuzes I have mentioned
above have been and are currently used by the Royal Canadian Artillery.
Propellant is the primary source of initiating the chain reaction to accelerate the
projectile through the bore. The first to be created was black powder or also know as gun
powder which is a low explosive consisting of intimate mixture of potassium or sodium
nitrate, charcoal and sulphur (RCAS). It is useful due to its ease of ignition and the high
rate of burning at low pressures. It is a shock insensitive explosive but very sensitive to
flame or sparks as well as friction (RCAS). The origins of black powder are uncertain but
are believed to be created from China (About.com). After the Mogols conquered China
they technology soon spread throughout the Middle East and into Europe. Over centuries
of improvements to gun powder large amounts were required to fire projectiles. In 1846
Nitrocellulose also known as guncotton was discovered (Brtianica, Nitrocellulose). At the
same time Nitroglycerin was discovered. Individually nitrocellulose is defined as a
single-based propellant. Combined with nitroglycerin this compound is classified as a
double-based propellant. This double-based propellant provides more power and stability
than guncotton and black powder. Triple-based propellants incorporate nitrocellulose,
nitroglycerin and nitroguanodine (RDECOM, 6). The need for a more concentrated
propellant is to have a slow burning, low heat, with high velocity output on a projectile.
Low explosive propellants are burn at a lower rate than High Explosives (HE) which
causes gases to build up which propel the projectile at a higher velocity. High explosives
are used for more disruptive actions (RCAS). These can be used as boosters, bursting
charges and as an initiator. Low explosive propellant burns at a rate for desired projectile
velocity, ballistic regularity and safe maximum chamber pressure. In the Royal Canadian
Artillery the ideal propellant: has a regular and controllable burning, be smokeless and
flashless, leave no residue, free of poisonous fumes, cause minimal gun erosion, easy to
ignite, be stable in storage, insensitive to shock and friction, no effected by moisture or
temperature, capable of rapid and easy manufacture, safe to manufacture and provide
maximum power for minimum bulk. The Royal Canadian Artillery uses a single-based
propellant. I will discuss the propellant for the 105mm M67 propellant. It consists of
seven charges. Charges one to two are single perforated which are quick burning. Charge
three to seven is multi-perforated which is for progressive burning. Charge five
incorporates a decopperizing agent to keep the bore clean. As seen in Annex E is an
example of single and multi-perforated grain propellant. These grains like propellant are
contained in cloth bags and labels accordingly to charge, which is determined by weight
(Annex F). The propellants are connected together with twine and can be separated to
meet the requirements for the range and projectile type to be fired. There are many other
types of propelling charges for different calibre of weapon systems. Sometimes the initial
pressure caused by the propellant will not achieve the range required. In this instance
there are other means such as rocket assisted rounds which ignite during flight to cause
The use and combination of the evolution of artillery weaponry; projectile shape
and construction, fuze functionality and propelling charge effectiveness gives the artillery
gunner the ability to accurately place a projectile on time and on target. The combination
of the advances allows for precise accurate delivery of various types of ammunition in the
artillery arsenal. The artillery projectile can travel further with more accuracy with the
ability to detonate above ground, underground or precisely when it hits a desired target.
The fuze has allowed artillery projectiles capabilities such as delivering illumination
rounds to mark targets for engagement, illuminate potential enemy locations. It also
allows for the delivery for smoke rounds which can screen friendly movement or blind
the enemy. Over the course of 900 years the evolution of artillery weapons and the
delivery system has greatly improved. With the introduction to more complex weapon
systems such as the M777`s Excalibur round the future holds the potential for more
advanced and more efficient weapon system and delivery methods.
Annex Annex A. Shoulder Base Plug Driving Band
Hogg, Oliver Artillery: Its Origin, Heyday and Decline.
RDECOM, The Evolution of Artillery for increased Effectiveness
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