PROPELLANT CHARGES & CURRENT TRENDS Flashcards
The different types of propelling charges are:
Fixed
Semi-fixed
Separate
what is a Fixed Ammunition
Ammunition where the cartridge case is permanently fixed to the
projectile
The propellant is completely enclosed
The following factors affect the choice of
fixed ammunition:
Fixed charge weight (direct fire).
High rate of fire / automatic loading.
All up weight and size of round should not make handling difficult.
explain Semi-fixed Ammunition
the projectile is loose fit into the cart case.
This enables charge adjustments to be
made.
Considerations with Semi- fixed type of system are:
Charge can be adjusted so this type of system is used in most indirect fire weapons.
Ammunition is easily handled.
Stowage problems in AFVs may be eased.
Use of more than one type of charge.
Explain separate ammunition & give an
example.
The projectile and the charge are packed
separately and only joined in the chamber of
the gun.
155mm Howitzer ammunition.
Explain Bagged Charges
This charge system utilises obturation
provided by the gun.
The characteristics of semi-fixed separate ammunition
apply with the addition of the following:
No cart case to be extracted.
Breech slightly simplified.
Fume extractors can work more effectively.
Additional component loaded Tube vent.
Weight is less.
Easy charge adjustment.
Four types of bagged charges:
Equal Cylinders
Unequal Cylinders
Stem and Ring
Stem and Segment
Design Considerations for bagged charges
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 are the two design principles of Bagged
Charges?
The lowest charge must be stable so it does not lose
its shape when loaded alone and cause a misfire or
delay in complete ignition.
The igniter, which is always fitted over the lowest
charge is made of the largest possible diameter.
What is the difference between a Combustible
and Consumable cart case?
Consumable. Material that is used up during the
process of the combustion of the propellant. It is an
inert material and does not contribute to the explosive
process.
Combustible. Material that is capable of burning and
contains ingredients that contribute significantly to the
production of propellant gasses.
What is De coppering?
The process of cleaning the bore of the weapon
of copper deposits left by the driving band.
Two types of Cartridge Cases
Combustible
Consumable
Define Consumable Material? Consumable cart case.
Material that is used up during the process of
the combustion of the propellant. It is an inert
material and does not contribute to the
explosive process.
Combustible Material
Material that is capable of burning and
contains ingredients that contribute
significantly to the production of propellant
gasses.
