Cartridges and Projectiles Flashcards
What are the non metallic natural fibres?
CELLULOSE
SILK
WOOL
RUBBER
What are the two main types of plastics?
Thermoplastic
Thermosetting plastic
(Third is engineering plastic)
What are the two types of defects in metals?
Mechanical
-Cracking due to stress
Chemical
-Corrosion due to impurities
What is the definition of corrosion?
The conversion of a metal to a non-metallic state.
What are the types of corrosion?
Rust (Ferrous Oxide)
Aluminium Oxidation
Cupric Azide Contamination
Zinc Exudation / ‘Free Copper’
MAZAK Contamination
What are the methods of HE filling techniques?
Casting
-Straight pour
-Creamed
-Liquid and biscuit
Pressing
-Pressing
-Incrementally into case
-Pre pressed charges
Extruding
-Direct extrusion into case
Pre forming / cocooning
-Land mines
What is the CWR for modern HE?
20% - 30%
What are the disadvantages to using the hot melt process?
Shrinkage
Cracking
Dusting
What compounds are used for the coating of
the internal Shell walls?
Shellac
Varnish
Lacquer
Bitumen
Resin
What are the 4 requirements for tracer composition?
Luminosity
Strength
Consistency of performance
Ease of Ignition
What are the 3 classifications of tracers?
Tracer Projectile
Tracer and Igniter Projectile
Integral Tracer
What are the two means of ignition for tracer rounds?
Direct Ignition
Propellant Ignition
What are the types of primers?
Percussion and electric
The amount of gunpowder used in the
magazine depends upon what?
Chamber dimensions of the gun
Size of the Propellant charge and the Case in which it is ignited
What are the components of a conducting cap?
Base
Pole unit
Cap
Magazine
What is the definition of a round?
A complete assembly of a projectile (with or without fuze), a propellant charge in a cartridge case, and the means of igniting the propellant charge.
What is the definition of a projectile?
An object capable of being propelled by a force, normally from a gun, and continuing in motion by virtue of its kinetic energy
What are the three types of projectile?
Shot
Shell
Carrier
What are the components of a projectile?
Cavity
What are the three classifications of projectiles?
Training
Operational
Weapon functioning/inspection
What are the 5 operational projectiles?
Shot
Shell
Mortar
Grenade
Bullet
What are the 3 functions of a driving band?
To centre the projectile in the bore and impart spin
To prevent the forward escape of propellent gases
To assist in prevention of slip back of the projectile when loaded at high elevations
What are the 6 requirements of a driving band?
No excessive pressure on the shell or barrel
Cater for change in bore diameter (wear)
Remain firmly attached to the projectile
Must not alter the ballistic shape of the projectile (engraved state)
Cause no excessive friction or bore wear
Simple to make and fit
What are the methods of attachment for a driving band?
Split ring
Solid ring
What are the types of driving band?
Orthodox band
Modern band
Gas check type
Double band
Probert
(OMGDP)
What are the methods of preventing twisting in driving bands?
Wavey rib
Knurling
What are the types of cartridge systems?
Breech loading
Quick firing
What are the types of quick firing cartridges?
Separate
Semi fixed
Fixed
What are the 3 components of breech loading gun ammunition?
Primer
Charge bags
Projectile
What are the three different types of propellant charges?
Fixed
Semi-fixed
Separate
What are the four types of bagged charges?
Equal
Unequal
Stem and ring
Stem and segment
What are the design considerations for charge bags?
Be non smolder
Be non stretch
Be non wear
Be entirely consumed on firing.
Leave no smouldering particles or residue.
Be insect / vermin / rot proof
Be permeable to the flash from the tube
What are the charge bag types IRT their function?
Normal
Super
Reduced
Fractional
Incremental
Blank
De- coppering
What is newtons third law?
For every action there is an equal and opposite reaction.
What are the two designs for RCL ammunition?
Blow out disc
Perforated cart case
What are some advantages of RCL systems?
No recoil
Low weight
Man portable
Mounted on light vehicles
What are some disadvantages to RCL systems?
Flash/Dust (BBDA)
Low velocity
Large propelling charge
What are the three methods used to attach projectiles to cartridge cases?
Coning
Canneluring
Both
What are the factors that affect shell design?
Strength to withstand firing stresses
User requirements
Ballistic performance
Safe handling ,transportation and storage
Economy in manufacture
Target effect
(SUBSET)
What are the ways to manufacture HE shells?
Normally steel
Cast
Forged
Extruded
What are the 7 forces that act on a projectile during firing?
Gas pressure
Acceleration
Setback
Heat
Centrifugal
Driving band pressures
Side slap
What are the methods of operation for carrier shells?
Bursting
Base ejection
Nose ejection
Base emission
What is the difference between a gaine and an exploder?
Gaines pass on detonating wave
Exploders enhance detonating wave
What is the make-up of a brass cart case?
Copper 70%
Zinc 30%
How is obturation achieved in Quick fire and breach loading cartridges
QF - uses the cart case to provide obturation
Breech loading - rearward obturation is achieved by the gun
What are the materials used to make CCC?
Nitrocellulose
Kraft paper
resins
What is the reason brass is used in cart cases?
Performs well in most equipment
Metallurgy and techniques are well known
Does not corrode to give hard abrasive particles
What are the advantages to CCC?
Everything loaded into the chamber plays some part in ballistics
Suitable material gives a boundary layer of gas which is cooler then the propellant gas
Reduces barrel wear
Reduced cook off with low charges
What are the methods of sealing tracer rounds?
Brass or Celluloid discs or cups
Nitro glycerine and Carbamite
Bakelite discs
How does a rocket assist work?
A rocket motor and venturi is attached to the base of the projectile that when ignited provides thrust.
How does a base bleed work?
A pyrotechnic attached to the base of the projectile that when ignited produces gas to fill the low pressure area at the base to reduce drag.
How is a quick fire-seperate round loaded?
Proj and cart case packed seperately
loaded as 2 units
Proj is rammed before cart case is loaded
How is a quick fire semi-fixed round loaded?
PROJ and Cart case packed together
Mated together and Loaded as one unit
Projectile rammed by Cart case
How is a quick fire fixed round loaded?
PROJ and Cart Case joined together
Loaded as one unit
Rammed as one unit
What are the applications of cellulose?
Used with charge bags and pyro’s
What are the types of Varnish?
Copal varnish
Shellac
What are the applications of Rubber?
Rubber composition bitumen is widely used in Squash Head
What are the applications of Wool?
Felt pads
What are the applications of Silk?
Used to tie bundles of cordite to form propellant charges, Make bags for loose prop charges
Explain the action on firing for the conducting cap.
Round loaded into gun, breech closed, electric needle
moves forward on to the Primer Contact
On Firing , current flows through the needle ,contact
piece & pole unit to the pole piece of the cap.
The filling in the cap is a conductor due to the inclusion
of graphite, permitting current to pass through this to the brass distance piece & outer case of the cap, and back through the body of the base, Cart Case, gun to
complete the circuit
Heating occurs, composition ignites to produce a flash in the Magazine
What are the 4 requirements of the cartridge case?
Protects contents
Easy loading and extracting
Provide obturation
Able to house primer
