Summative Assessment 2 Flashcards
What are the ingredients of Greek Fire?
Naphtha, Sulphur, Pitch
What are the main ingredients of the Chinese gunpowder?
Saltpeter, Sulphur, Charcoal
What was Roger Bacons importance in regards to the development of explosives and when?
He described the composition of the gunpowder and experimented to improve its quality and explosive power in 1242
Gunpowder Grains loaded in a gun had sufficient room between then for what purpose?
To allow the flash to reach them all at the same time.
HMX was initially a side product of what HE?
RDX
What is the British name of the adopted filler Picric Acid?
What year was Picric Acid first discovered
Lyddite
1742
PETN is currently widely used as a secondary explosive in what in service EO?
Det Cord
Name the 3 early methods of rifling?
Hexagonal or Whitworth Rifling Studded (woolwich) Rifling Lead Coated Shell French Rifling Oval Bore Vavasseur’s Driving Band
When did cast iron barrels become prevalent?
16th Century
Who designed the first modern combustion time fuze?
Colonel Boxer
Why were trunnions an important improvement to weapons?
Absorbed some of the recoil shock, Allowed the gun to be raised and lowered for firing
Who invented the Breech Loading Gun?
Sir William Armstrong
Who is credited with the concept of a gun?
The monk Black Berthold
What term is used to describe the diameter of the bore excluding the depth of the grooves?
Calibre
There are two types of muzzle brakes, and their forms?
Built up and Solid forging & Swaged - double baffle, single baffle
A decrease in the initial resistance to shot start is caused by what and what effect will this have?
Barrel wear and Range is decreased
What are the 2 categories of breech mechanisms?
Screw mechanisms and Sliding Block mechanisms.
Screw mechanisms are typically used with Breech Loading systems which fire separate ammunition.
Sliding Block mechanisms typically used with Quick-Fire system, and require semi-fixed or fixed ammunition (CC)
What do fume extractors aid in?
To prevent the fumes entering the crew compartment
What is the desired result when using delay fuzing on HE ammo?
To achive a much greater cratering affect which can be used to penetrate OHP and enhance to destructive blast effect detonation.
What are the 5 basic requirements of artillery?
- Range
- Ammo
- Accuracy and Consistency
- Mobility
- Protection
Why do we carry less illuminating ammunition?
- Image intensifiers
- Low light television
- Thermal Imaging
- Infra- Red sights
What are the two main methods used without altering the weapon system to increase range?
- Ballistic coefficient
- Post firing boost- Rocket Assist/Base bleed
Define the word accuracy?
Define the word consistency?
Accuracy: The measurement of precision with which the MPI, of a group of rounds can be placed on a target.
Consistency is a measure of spread of rounds around the MPI when rounds are fired from the same gun at the same elevation.
State 4 variations that affect consistency?
- Muzzle velocity
- Ballistic Coefficient
- Weather conditions
- Laying, ramming and wear to the gun
Why is the trend now to exclude gun shields from modern towed equipment?
Air portability and keep weigh to a minimum
What is the abbrevation of Composition Explosives?
CE
Is the dust or explosive residue hazardous to health?
Yes
What is the definition of HE?
“A substance, alone or mixed with one
another which are in a metastable state and
are capable for this reason of undergoing a
rapid chemical reaction without the
participation of external reactants such as
atmospheric oxygen”.
The preferred method of stabilisation of motar rounds is (a)______________ stabilised. (b) ____________ stabilisation is not preferred because it increases the mechanical complexity of the weapon and (c) _________________ the rate of fire.
A- Fin
B- Spin
C- Reduces
What have some of the considerations that have to be addressed before choosing a weapon system?
- Nature of the task
- Terrain
- Effect required at target
- Range
- Mobility
- Protection
What is the major advantage of FFR when employed as indirect fire support weapons?
Large rate of fire in the short period of time.
Why is “bed in” a mortar a disadvantage?
- Minimum of two rounds required which wastes ammunition
- Compromises the position
Define a Mortar?
- Is a weapon
- Recoil force transmitted to the ground through the base plate
- Usually smooth bore
- Muzzle loading
- Firing a fin stabilised bomb
- With propelling charges
- At low MV and high trajectory
What are the main components of a mortar bomb?
- Bomb body- including fuze and provides obturation
- Tail Unit- propulsion system
What are the two types of augmenting cartridges?
- Thin leaves of plasticised and bonded propellant stapled together- US 120mm Mortar
- Hollow plastic cartridges containing granular propellant- Horse Shoe
What is a carriage?
A carrigae is ordnance which travels on its wheels and fires with its wheels in contact with the ground.
What is a mount/ mounting?
A mounting does not fire with its wheels in contact with the ground.
What are the 2 types of mounting?
1- Mobile- Towed with wheels reomved or raised for firing
- Self propelled- Built into an open or closed tracked hull.
Functions of a carriage or mounting?
- Provides mobility for transportation
- Support ordnance and give stability
- Give ordnance direction in elevation and traverse
- Provide accurate and quick laying to ordnance
- Absorb recoil energy and return gun to firing postiion
What are the 2 main parts of a carriage and mounting and describe their function?
- Superstructure- Supports the ordnance in firing position, gives direction in trasverse and elevation, provides axial movement for recoil and siting system
- The Basic Structure- The part in contact with the ground and transferring the firing stresses.
Define a superstructure?
S- Saddle
C- Cradle
R- Recoil system
B- Balancing gear
E- Elevating gear
T- Traversing gear
S- Sights
What are the 3 types of cradles?
1- Trough type
2- Ring type
3- Open structure- Skeleton type
What are the 2 parts of the Recoil system?
1- The buffer- Controls the reward movement of the recoiling parts
2- Recouperator- Mechanism that return the recoiled parts to their original position and holds them until the next round is fired.
What are the 3 types of elevating gears?
1- Worm and segment
2- Nut and screw
3- Arc and pinion
What elevating gear did the Hamel Gun use?
Arch and pinion
What are the 4 traversing gears?
1- Nut and screw
2- Arch and pinion
3- Worm and segment
4- Rapson nut and screw
Define Basic structure?
1- Trails
2- Saddle Supports
3- Articulations
4- Spades
5- Platforms
6- Wheels and axels
7- Suspension and brakes
List 4 types of trail types?
1- Pole trail
2- Split trail
3- Box trail
4- Bowed box trail
What are the advantages of a mortar?
1- Moderate cost
2- Low weight
3- Simplicity
4- High angle and rates of fire
What are the disadvantages of a mortar?
1- Long time in flight
2- Relative inaccurate
3- Dependence on ground conditions
4- Degraded performance in wet conditions
5- Lack of protection for mortar crew
What are 2 ways fragmentation in a mortar can be influenced?
Bomb wall produced in metal with good fragmentation qualities
Thin walled liner with pre-cast fragments.
What are the 4 different fuze types for a mortar?
1- Impact/ Point Detonating (PD)
2- Delay (DEL)
3- Mechanical time Super Quick- (MTSQ)
4- Proximity (PROX)
What is a windage?
The gap between the outer wall of the bomb and the inner wall of the tube.
What is Yaw?
This is accentuated by the turbulence outside the muzzle. The expanding propellant gases accelerate past the bomb and start to become unstable near the fins.
What is the maximum range achived for a mortar?
800mils
What is the maximum safe elevation (minimum range) for a mortar?
1420mils
T or F
Can mortars be fired at zero range if they are fired at or close to an elevation of 1600mils?
True
What are the Calibre and the categories of mortars?
1- Light Mortars- 50- 70mm
2- Medium Mortars- Up to 100mm
3- Heavy Mortars- up to 120mm
4- Gun mortars- Unconventional- Gun or mortar- breeche loading, rifled barrels, recoil systems.
What are the fuzing functions for a projectile?
1- Air burst
2- Delay
3- Ground Burst
There are 4 types of carrier projectiles, what are they?
1- Smoke
2- Smoke WP
3- Illumination
4- Sub- munitions
What are the advantages of using “smoke”?
1- Screen movements
2- Marking targets
3- Blind the enemies observation
How do we increase range of a projectile?
1- Ballistic co-efficient - Base bleed
2- Post firing boost - Rocket Assist
Accuracy of firing a projectile may be affected by many sources, name them?
1- Survey of guns
2- Accuracy of target location
3- Inaccuracy inherent to the ammunition and instruments
4- corrections applied for external conditions
Consistency of firing a projectile may be affected by many sources, name them?
1- Muzzle velocity
2- Ballistic Coefficient
3- Weather Conditions
4- Laying, ramming and wear on the gun
What are the conventional design features of a mortar?
- Smooth bore
- Muzzle loading
- No recoil mechanisims
4- Restricted to firing above 45 degrees
5- Cannot be fired in direct role
What are the unconventional design features of a mortar?
1- Rifle bore
2- Breech loaded
3- Low angle fire
What are the 2 main parts of a gun?
1- The carriage or mounting
2- The ordance
What is the function of ordnance?
Provides a vessel to contain the force of burning charge in such a way that the energy produced is transmitted safely and predictably to the projectile.
What are the main components of the ordnance?
1- The barrel and its attachments
2- The breech
3- The firing Mechanism
How do you measure the calibre?
The calibre of the barrel is defined as the diameter of the bore from land to land.
What are the 2 types of rifling?
1- Progressive
2- Constant
What are the 5 construction techniques for a barrel?
1- Monobloc
2- Composite Barrels
3- Loose Barrel/ Loose Liner
4- Built Up Barrels
5- Wire Wound
What are 2 types of breech mechanisms?
1- Interrupted Screw mechanisms
2- Sliding Block Mechanisms
Whata re the 3 types of sliding block mechanisms?
1- Tied Jaw
2- Open Jaw
3- Closed jaw
What are the three firing mechanisms for a gun?
1- Percussion
2- Electric
3- Electric and percussion
When did the cast iron cannon come into use?
16th Century
What are the 6 early variations of rifling?
1- Vavasseur’s driving band
2- Woolwich Rifling- studded
3- Oval bore
4- French Rifling
5- Hexagonal or whitworth riflinh
6- Lead coated shell
When and where was the first fully self contained SAA cartridge created?
Paris- 1808
When was greek fire created?
7th Century AD
What is greek fire made out of?
1- Sulphur
2- Naphtha
3- Pitch
When was black powder created?
9th century
What is black powder made out of?
Saltpeter (potassium nitrate)
Sulphur
Charcoal/ resin
When was the first smokeless powder created?
1865
Who created ballistite and in what year?
Alfred Noble in 1887
What does Ballistite consist of?
Camphor (wax)
NG- Nitroglycerine
NC- Nitrocellulose
What does cordite consist of?
1- NG- Nitroglycerine
2- NC- Nitrocellulose
3- Petroleum jelly
What are 2 types of smokeless propellants?
Cordite
Ballistite
Name the modern smokeless propellants?
Single based, double based, triple based and composite based propellants
When was fulminate mercury discovered?
17th century
What is Mercury fulminate used for?
Detonators
What is in Dynamite?
NG- Nitroglycerine
What does guncotton consist of?
NC- Nirtocellulose, Nitric Acid and cotton fibres
What is Tetryl used for?
Booster
Too sensitive to be used for a main charge
What is PETN used in currently?
Who and when developed it?
Det cord
Germans, 1891.
Describe FAE?
Fuel Air Explosion
Over pressure plus heat = Thermobaric
What are the different types of Direct Fire systems?
- Small arms- smaller than 20mm
- Cannon- greater than 20mm
- Rockets
Define a Recoiless System?
- 84mm M3 Carl Gustaf
- Man Portable
- Versatile payload
- Limited armour penetration
- Large firing signature
Define Guided Missiles?
- Greater accuracy
- High velocity
- Increaded cost
- Specific target types
How do you increase the velocity of a mortar?
Use larger propelling charge as well as a longer barrel.
Who designed the first modern combustion
time fuze?
Colonel Boxer
Grained gunpowder was produced in what year?
1630
Corned gunpowder was created where, and in what year?
France, 1429
What is the distance between the centre of pressure (COP) and the centre of gravity (COG) called?
Static Pressure
What are the three methods of Articulation for Trails
Ball Socket Joints, Rocking Arms, Pins
How do you determine Calibre length
You divide the length of the barrel by the Calibre diameter of the bore.
What are the five stressors
Torsional, Radial, Girder, Longitudinal, Circumferential
What are the Charge to Weight Ratio (CWR) Limits?
Artillery no more than 15% Mortars 20%>
What are the two types of Mortar Cartridges?
Primary Cartridge and Augmenting Cartridge
How large should a static margin be?
At least the equivalent of one calibre.
What did Sir William Armstrong invent?
The first Breech loaded gun
What did Henry Shrapnel invent and when?
Hollow cannon ball filled with shot which burst mid-air, 1784
List some Issues with early firearms like the Martini Henri, and the improvements made to overcome them with newer designs like the Mauser and SMLE.
Issues: excessive smoke and residue from black powder main charge. Poor/weak cartridges led to cartridge extraction problems
- Improvements:
- Smokeless powder
- improved cartridge cases
- better ballistics and projectile design
- Weapons improved accuracy and stronger breech.
What developments did self contained cartridges lead to?
Revolvers, pistols, and later rapid fire single shot rifles, including magazine rifles following into machine gun development.
What is meant by ‘Survey of the guns”
The process of determining the relative horizontal and vertical locations of the guns and their target in order to provide accurate data for the firing chart(computer).
What are some difficulties of incorporating safe fuzes in mortar boms?
- Lower set back forces compared to guns
- No centrifugal forces (fin stabilised, no spin)
*
What fuse safety features are used mortar bombs?
Delayed arming mechanisms - propeller spin ( minimum distance travelled) to arm fuze. Minimum required acceleration to arm fuze.
Safety lock - pin required to be removed prior to firing.
When was Nitroglycerin discovered, and by whom?
1846 by Sobrero
Who invented TNT, and when?
The Germans in 1863, used as a yellow dye.
What was the makeup of early roman Gunpowder?
Ref: History of Ammunition Weapons, slide 8.
7 parts saltpetre
5 parts young hazel twig
5 parts sulphur
“But of saltpetre take seven parts, five of young hazel twig (use to make charcoal) and five of sulphur, and so thou will call up thunder and destruction if thou know the art”
What was the first metal cannon and when was it employed?
The Pot-de-fer.
First used by the French in the 100 years war 1337-1453
In 1346, the first recorded battle in England where artillery was used took place.
What was the name of the weapon used?
The ‘Crecy Bombard’
When were the first metal or iron balls being used as projectiles?
The mid 1400’s.
The advantages over stone were consistency and penetrating power.
What year was Corned Powder invented?
Why was this significant?
1429.
Significant as:
Corned gunpowder was less susceptible to the wet,
Left less residue in barrels,
Older gun designs couldn’t handle the increased pressure generated by corned gunpowder, and lead to faster development of the cannon.
When was the interrupted screw breech invented?
1845.
Developed to form an effective gas seal at the breech for breech loaded weapons at the time of firing.
After the invented of the interrupted screw breech, what further developments were made?
In 1890, Alex Welin developed a stepped interrupted screw design. This is still in use today on bagged artillery systems.
Further obturation development was made in the form of the De Bange breech obturator system, also still in common use.
In what decade were rimfire cartridges developed?
1850’s
In what year were centrefire cartridges developed?
1857
Why was the development of self contained cartridges significant?
Allowed for development of revolvers (later pistols), and rapid firing (for the time) single shot rifles (late magazine fed rifles).
This later led to early gen machine guns (Vickers, Maxim)
What was the first mass-produced needle gun/Gun fired by pin?
1865 Dreyse Needle Gun Mechanism
When was the lever action, single shot Martini-Henri rifle introduced? What problems did it encounter?
Suffered from extraction issues due to weak cartridge cases, and excessive fouling due to use of black powder as the main charge.
What was the significance of the 1898 Mauser?
Standard weapon for German Army in WW1 and WW2.
Basis for many other centrefire rifles due to high accuracy and strong breech.
Maximised advantages of smokeless powder, cartridge case construction, ballistics and projectile design.
What was the significance of the Short Magazine Lee Enfield (SMLE) rifle, which entered British service in 1907?
The next generation of centrefire rifles.
Maximised on technical advantages on ballistics, cartridges cases and projectile design.
Used by Commonwealth forces in WW1, WW2, Korea.
What is ‘Shot Start’?
The moment the projectile begins to move inside the bore.
When was the Carcass developed, and what was it’s significance?
1672 - the forerunner of incendiary devices.
