LO8 - Theory of Design Flashcards
REMEMBER THIS QUESTION
Definition of SAA.
Small arms ammunition is normally defined as, “Ammunition for weapons such as pistols, rifles and machine guns below 20 mm in calibre”.
REMEMBER THIS QUESTION
In SAA, a complete round is normally made up of the following 4 main parts
- Cartridge case
- Ignition system
- Propellant charge
- Projectile
Explanation of different parts of SAA
Cartridge Case - Designed to hold the propellant charge, incorporate the ignition system, retain the projectile and provide obturation
Materials used in SAA
Generally made from ‘ cartridge brass ‘ although aluminium, cupro nickel or steel may be encountered
Cartridge Brass –70/30 copper/zinc alloy
REMEMBER THIS QUESTION
Soft mouth necessary for the following reasons:
- Expand as soon as pressure rises in chamber
- Establishes an early seal
- Prevents gas leakage
REMEMBER THIS QUESTION
Hard base necessary for the following reasons:
- Enable case to withstand internal pressure and rearward thrust from propellant gases
- Stresses applied by extractors
- Chambering/rechambering rounds
- Extraction of empty cases
Methods of securing bullets to cart case
- Press fit
- Canneluring
- Indenting
- Stabbing
- Coning
- Crimping
Types of ignition system in SAA
- Berdan
- Boxer
- Rim Fire
Propellants used in SAA?
- Single and double based propellants
- Double based are 15 – 20% more energetic but increase erosion
- Modern double base propellants contain less Nitro-Glycerine (NG) to reduce wear
- NATO 5.56mm contains Nobels Nitro-Neonite (90% NC, 8% NG), Carbamite which acts as a stabiliser and coolant and graphite, a surface cleaner and moderant
Design of projectiles is governed by its what?
- Target characteristics
- Effect required on the target
- Maximum effective range
- Ballistics
- Type of weapon
Colour coding of projectile tips
- Black – AP
- Silver – API
- Blue – Incendiary
- Yellow – Observing
- Red – Tracer
- Uncoloured - Ball
REMEMBER THIS QUESTION
Explain set up
- Forward obturation by base expansion of the projectile by propellant gases.
- Efficient if the projectile has no boat tail
Definition of grenade
A grenade is a small explosive store designed for projection by hand or from a personal weapon”. Occasionally a special discharger or launcher may be used.
REMEMBER THIS QUESTION
Design Categories of grenades
- Hand Thrown.
- Projected - Rifle launched/gun fired.
- Discharger- Weapon/vehicle launched.
REMEMBER THIS QUESTION
Different payloads in a grenade
- High Explosive Anti-Personnel.
Defensive
Offensive. - High Explosive Anti-Tank. (HEAT) and Dual Purpose.
- Smoke.
- Chemical or Irritant.
- Flash or Noise composition - (Stun).
- Incendiary.
- Practice.
- Illuminating.
REMEMBER THIS QUESTION
Typical components of a grenade
- Body
- Filling
- Fragmentation
- Fuze Cavity
- Fuze
What is an offensive grenade
- Offensive grenades rely solely on the effect of blast for their anti-personnel effect.
- To cause any physical damage to a man, a blast grenade must burst very close to him or at least in a confined space with him.
- Their usual effect is to stun or disorientate a man so that he is incapable of rational reaction for a short period of time.
what is a Defensive grenades
- These grenades are designed for use when the thrower is fully or partially protected in a defensive position.
- The large lethal area is achieved using fragments projected at high velocity.
What are screening and signaling smoke grenades?
- Screening Smoke grenade is designed to produce a dense curtain of smoke masking the removal or deployment of personnel in tactical and training situations.
The original screening grenade had a White Phosphorous (WP) fill with a HE disruptive fuze that burst the casing on initiation. - Signalling smoke grenades are used for a variety of signaling purposes and operate in the same manner as an igniferous initiated screening grenade.
What is an Chemical/ Irritant grenade anti-riot?
- Filled with lachrymatory or irritant compositions.
- The emission principle is rarely used now, since rioters tended to throw them back!
- Current designs utilise a rubber body containing a large number of primed CS pellets, that on initiation, create gas pressure bursting the body, and spreading the pellets.
What is Flash or noise - stun grenades?
- The police and special forces use stun or disorientation grenades as a non-lethal weapon.
- They incorporate pyrotechnic powders which produce high noise (in excess of 130 db) and flash values sufficient to disorientate anyone in the vicinity.
- Designed to produce no fragmentation.
- Stun and disorientate.
- Blinding flash load report and mild blast.
- Single or multiple functioning.
Incendiary grenade
- Used for numerous tasks, including;
as an IEDD Tool
as an initiator - Body colour normally RED
Describe Illuminating grenade
The illuminating grenade is primarily used by police and Search and Rescue (SAR) teams
and can be operated as both a trip flare and grenade.
What is a Discharger grenade?
- Originally fitted on AFVs to provide an immediate localised smoke screen, their use has now extended to Anti-riot and HE fragmentation variants.
- Electrically initiated, they have a small propelling charge that simultaneously ejects the grenade from the discharger barrel and ignites the main filling.
What is a Projected grenades
- Ever since the introduction of grenades many methods of increasing their range have been developed.
- Projected grenades are categorised as either Rifle or Weapon launched.
What are normal means of delivery of grenades?
- Hand Thrown
- Projected
Rifle launched
Gun fired - Discharger
Weapon launched
Vehicle launched
REMEMBER THIS QUESTION
ADVANTAGES of RCL
- NO RECOIL
- LOW WEIGHT
- MAN PORTABLE (84MM)
- Can be mounted on vehicles
REMEMEBER THIS QUESTION
DISADVANTAGES of RCL
- LOW VELOCITY
- FLASH / DUST SIGNATURE
- LARGE PROPELLING CHARGE
Characteristics of 84MM Carl Gustav RCL gun.
- Two man operated
- Breech loaded
- Percussion fired
- Recoilless gun
- Primarily an armour defeating weapon but can be used against emplacements and hard targets
REMEMBER THIS QUESTION
Different types of EO used in 84mm Carl Gustav
- HE
- HEAT
- HEDP
- SMK
- ILLUM
- ASM - Anti Structural Munition
- PRAC
- Sub calibre (6.5mm, 7.62mm, 20mm)
In the RCL system, the breech obturator is replaced by what?
Venturi
State the principle of RCL?
If two weights can be fired at equal velocity then the weapon will be recoilless.
FFR are made up of 2 main sections and one
other item, what are they?
- Motor including the igniter, combustion chamber , fins (if applicable) and nozzle
- Warhead (including the fuze)
- The Launcher
REMEMBER THIS QUESTION
Components of rocket motor in FFR
- Casing
- Combustion Chamber
- Propellant
- Igniter
- Nozzle (s)
- Fins (if not spin stabilised)
Why are solid propellants preferred over liquid propellants in FFR’s?
Due to reliability and simplicity in use.
REMEMBER THIS QUESTION
What are the different types of warheads that can be used in FFR’S?
- Nuclear.
- HE.
- Chemical (including smoke).
- Pre-formed Fragments.
- Sub Munitions.
- Terminally Guided Munitions, and
- Practice munitions.
Factors affecting rocket accuracy
- Surface Cross Winds
- Propellant Burning Rate
- Launcher Induced Errors
List four characteristics of FFR motors.
- Only use boost motors (high energy release over a short time span).
- Motor casing must be strong enough to withstand the pressure and temperature of combustion.
- Usually made of various steels, however have been made from glass reinforced plastics.
- De Lavel nozzles normally used (convergent –divergent)
What is the main type of propellant used in FFR’s?
Solid Propellant
Types of Mortar fire
- Preparation fire;
- Covering fire;
- Defensive fire;
- Counter Battery fire;
- Harassing fire;
- Smoke (screening and blinding);
- Illuminating
What is a mortar?
Closed metal tube designed to project a bomb into the air so that it follows a predetermined trajectory
Easy & simple to handle and operate
Provides the infantryman with a light weight indirect fire weapon that is readily available
REMEMBER THIS QUESTION
Current in-service mortar rounds
- HE
- SMK WP and RP
- ILLUM
- TRG
Components of mortar
- Baseplate
- Barrel
- Bipod, Tripod, or Monopod
- Sight
REMEMBER THIS QUESTION
Four main characteristics of mortar
- Smooth Bore
- No Recoil Mechanism
- Restricted to use at elevations above 800 mils
- Muzzle loaded
REMEMBER THIS QUESTION
Different EO used in M777
- HE M107
- HE M795
- SMART DM702A1
- HE Excalibur XM982
- Illuminating M485A2
- WP M825A1
Different propellants used in M777
- M231 (MACS)
- M232A1 (MACS)
- Reducer Flash M2
- M3A1 Green bag
- M4A2 White bag
What is used to initiate the charge in M777
Percussion Primer M82
* Fill - 22g Black powder
* Colour- Brass
Definition of a mine
An explosive or other material, normally encased, designed to destroy or damage vehicles, boats or aircraft, or designed to wound, kill or otherwise incapacitate personnel. It may be detonated by the action of its victim, by the passage of time, or by controlled means.
Mine warfare
- Disrupts an enemy’s manoeuvre plan and deny him use of terrain
- Reduce the effect of attacker superiority in numbers and channel him into and retain him in areas where he can be defeated
- Significant casualties to enemy armour and increase the effectiveness of other anti- armour systems
Effects of mines
- Disrupt
- Turn
- Fix
- Block
Characteristics of mine systems
- All weather, 24hr capability
- Psychological effect
- Contribution to the destruction of the enemy
- CBRN resistant
- Cost effective
What are operational characteristics of mines?
- Sensitivity
AP - 8 - 50 Kg
AT - 200 - 250 Kg - Ease of laying
- Resistance of countermesures
- Delayed arming - to let the mine layer get away
- Sterilisation
- Self-neutralisation
- Self- destruct
- Remote Control (RC)
- Record and Marking
What are the logistics characteristics of mines?
- Safety
Storage (10 to 20 years), transport, lay and arm
Self clearance - Reliability
Over long periods, hostile environmental conditions
Detonate at the right time
REMEMBER THIS QUESTION
Components of a mine.
- Warhead
HE,
Shrapnel,
Shape charges/ EFPs - Sensor or fuze
Mechanical
Electronic - Safety and Arming unit
- Power source - usually electrical power
- Case
Different types of AT mines
- Pattern
- Scatterable
- Side attack
- Area defence
Different ways of attacking tanks with AT mines
- Top attack
- Side attack
- Belly attack
- Track attack
- Full width attack
Different types of AP mines
- Pressure activated/ Direct Contact AP mines
- Omni-directional Fragmentational AP mines
- Directional Fragmentation AP mines
2 approaches to manufacture Anti-helicopter mine (AHM)
- Produce a mine specifically designed to destroy an approaching helicopter with a Focused multi EFP warhead
- Fit an electronic fuze to an existing heavy fragmentation mine
Example of AHMs?
- AHM 200-1 & 2 (Bulgaria)
- DNG Giant Heli-shotgun (Austria)
Methods of laying mines
- Hand laying
- Mechanical laying
- Scaterrable Mine Laying Systems
- Vehicle
- Shielder - Vehicle Launched Scaterrable Mine Systems (VLSMS)
- Artillery - Multiple Launch Rocket System (MLRS)
- Aircraft
Methods of breaching mines
- Hand breaching
- Mechanical breaching
Rollers
Ploughs
Flail - Explosive breaching
- Electromagnetic breaching
- Python
- Rapid Anti-Personnel Mine Breaching System (RAMBS)
- Fuel Air Explosives (FAE)
What are the 4 types of bases that are used in service SAA?
- Rimmed
- Rimless
- Semi-Rimless
- Belted
What does the grain of SAA consist of?
- Chopped lengths of extruded propellant
- Spherical grains
- Discs
What are the 4 base markings on SAA?
- Manufacturer’s symbol
- Year of manufacture
- Calibre
- Model Number
What are the rates of fire for M777?
- Maximum: 4 rpm for 2 minutes;
- Sustained: 2 rpm;
- After 30 minutes the rate of fire is dropped to 1 rpm (the electronic thermal warning device [ETWD] may determine the rate of fire).
Tab data for M777
calibre: 39 calibre 155 mm tube;
overall length (includes breech ring and muzzle brake): 6870 mm;
barrel length: 6090 mm;
muzzle brake type: double baffle;
muzzle brake efficiency: 30 per cent;
construction: monobloc;
numbers of grooves: 48;
travel of projectile: 508 cm;
length of chamber: 102 cm; and
rifling: uniform, right hand twist, one turn in 20 calibres.
Fuzes used in 155mm HE, Excalibur and Illum.
- HE - PD, MT, ET, MOFA
- Excalibur - ET
- Illum - MTSQ, ET
