Ballistics

Question 1

Definition of internal ballistics

Answer 1

Study of operating process within the gun from the moment that the propellant is ignited until the projectile leaves the barrel

Question 2

Objectives of ballistics

Answer 2

Launch the projectile safely

Consistent performance between shots

Achieve highest possible muzzle velocity

Question 3

Define Pioberts Law

Answer 3

The surface of a burning propellant recedes layer by layer in a direction normal to the surface

Question 4

Characteristics of propellants

Answer 4

Burning rate
Pressure index
Co volume
Force constant
Ballistic size
Form function

Question 5

How to improve performance

Answer 5

Improve muzzle velocity -

alter propellant to increase temp and pressure

Question 6

How systems loose engergy

Answer 6

Projectile
Residue gas heat
Recoil
Engraving driving band
Unburnt charges and gases
Lost heat to gun

Question 7

Variations

Answer 7

Weight - > charge weight = > peak pressure < time to all burnt

Propellant size

Chamber capacity

Ignition temp

Shot start

Bore area

Multiple variations

Question 8

Define intermediate ballistics

Answer 8

The study of the transition from internal to external ballistics that occurs in the vicinity of the muzzle

Question 9

Gas flow field

Answer 9

Muzzle gas flow field has two phases:

• precursor blast field
  —- bottle shock
  ——— barrel shock
  ——— Mach disc
• main blast = once proj leaves the barrel there is formation of another bottle shock

Question 10

Bottle shock

Answer 10

Barrel shock

Mach disc

Question 11

Types of flash

Answer 11

Pre flash
Primary flash
Muzzle glow
Intermediate flash
Secondary flash

Question 12

Forces acting on a projectile

Answer 12

Center of gravity

Centre of pressure

Question 13

How to mitigate impacts of intermediate ballistics

Answer 13

Flash reduction methods - break the Mach disc and bottle shock

• muzzle device
  Type of propellant
  Propellant additives

Question 14

How does ceramics work

Answer 14

Defeats projectiles by reducing their KE through reducing nose mass while decelerating the fire

Question 15

Ways to overcome forces acting on projectile

Answer 15

Nose shape
Base shape
Base bleed

Question 16

Stability

Answer 16

Centre of pressure must be behind center of gravity

Question 17

Define terminal ballistics

Answer 17

The study of projectile behaviour at the target

Question 18

Two factors affecting penetration

Answer 18

Projectile velocity

Density

Question 19

Types of terminal effects

Answer 19

Armour penetration

Non lethal effect

Incendiary

HE blast and drag

Question 20

Elements of terminal ballistics

Answer 20

Kinetic energy
Projectiles physical properties
Target types

Question 21

Four phases of ballistics

Answer 21

Charge ignition

Combustion prior to projectile motion

Combustion up to all burnt point

Gas flow and projectile motion after all burnt point to muzzle