TERMINAL BALLISTICS OF SMALL ARMS

  

Terminal Ballistics in Small Arms

What are Terminal Ballistics?

Terminal ballistic deals with the behavior of projectile once it hits the target. Terminal ballistic is the study of penetration of missiles or projectiles in deferent types of the target such as solids as well as liquids. It is the study of wounding capabilities in animal tissues and human tissues. Also, it involves the studies of bullet resistant materials such as jackets and vests. The study involves the penetration of bullets in making holes in glass panes in windows, showcases, and buildings. The target may be soil, brick or wood.

In another words the terminal ballistics may be called wound ballistics if the target is the human body. This is an important aspect of terminal ballistics. Since different part of human body react differently to similar caliber projectiles with in the same velocity. Broadly speaking terminal ballistics are sub divided in to penetration potential. A projectile can penetrate various materials and wound ballistics which is the effect of projectile has on living tissues.

      I.          Penetration Potential:

Penetration potential in terminal ballistics refers to the ability of a projectile such as a bullet to penetrate a target upon impact. This is a key factor in understanding how effective a projectile will be in real world applications, particularly in military, law enforcement, and hunting contexts. The penetration potential is classified in two types Non-Living and Living targets.

 

Non- Living Targets – windows panes and glass doors, Windscreen of cars which are made of safety glass or laminated glass, tempered in the car side windows, Bullet proof and vests or jackets, Ricochet of bullets from surfaces of wooden and brick walls.

 

Living Targets – Living targets can be animals or human begins especially when firearms are used for murders or suicide resulting in injuries on the body as well as inside the body. The human body or animal body is not a uniform medium. It is about 80% water in the case of human beings which is not uniformly distributed. At places, there are bones, veins, nerves, muscles, or blood places which would be making vulnerability different places.

 

The penetration potential is influenced by several factors, including:

·        Projectile Mass: Heavier projectiles generally have more momentum and, therefore, higher penetration potential.

·        Projectile Velocity: The speed at which the projectile travels also play a crucial role. Higher velocity increases kinetic energy, which can enhance penetration.

·        Projectile Shape and Design: Pointed or streamlined projectiles tend to penetrate more effectively than blunt or flat nosed ones. Additionally, the design such as hollow point, full metal jacket affects how the projectile interacts with the target.

·        Material of the Projectiles: Harder materials like steel or tungsten can penetrate more effectively than softer materials like lead.

·   Target Materials: The density, composition, and thickness of the target significantly affect penetration potential. For example, a projectile might easily penetrate soft tissue but be stopped by armor or a thick barrier.

·        Impact Angle: A direct, perpendicular hit will usually result in better penetration compared to an oblique angle, which can cause deflection.

 

    II.          Striking Angle:

The striking angle or impact angle in terminal ballistics refers to the angle at which a projectile hits its target relative to the surface of the target. It is typically measured relative to a line perpendicular to the targets surface.

 

·        Normal Impact (Perpendicular): When the striking angle is 90 degrees, the projectile hits the target perpendicularly. This usually results in maximum penetration potential because the energy is concentrated on a small area without any deflection.

·        Oblique Impact: When the striking angle is less than 90 degrees, the projectile hits the target at a slant. This can lead to deflection, reduced penetration or even ricochet, depending on the angle and the materials involved.

 

  III.          Stopping Power:

·        Stopping power refers to a projectiles ability to incapacitate a target immediately up on impact. This is a critical measure in defensive and military scenarios.

·        Stopping power influenced by combination of energy transfer, cavitation, deformation, and the bullets’ ability to disrupt vital systems.

 

  IV.          Cavitation:

Cavitation occurs when a projectile creates a cavity or hole in the target tissue. There are two types of cavities.

·        Permanent Cavity: The hole left behind by the projectile, representing the direct tissue damage.

·        Temporary Cavity: A temporary expansion of tissue around the projectile path due to shock waves, which can cause secondary damage even if the tissue recoils afterward.

A temporary cavity is a temporary expansion of tissue that occurs around a bullet path when through a target. The bullet speed and energy cause the tissue to stretch outward, creating a large space that the bullet itself. Although the tissue eventually returns to its normal position, the stretching can cause additional internal damage.

 

    V.          Fragmentation:

Fragmentation occurs when a projectile breaks into smaller pieces upon impact. These fragments can cause multiple wound channels and increase the overall damage with in the target. Fragmenting bullets are designed to maximize damage by increasing the number of individual projectiles that create a multiple injury path.

 

  VI.          Deformation or Mushrooming:

Deformation refers to the change in shape of the projectile after it strikes the target. Bullets, particularly soft point and hollow point bullets are designed to deform or mushroom up on impact to increase the surface area, reduce over penetration, and maximize energy transfer to the target.

The main advantage of deformation increases the stopping power by creating a larger wound channel and transferring more kinetic energy to the target.

 Yaw:

Yaw describes the rotation or wobbling of projectile around its center of mass as it travels through a medium. In terminal ballistics, yaw can affect how the projectile interacts with the target, influencing penetration depth, energy transfer, and fragmentation.

The main disadvantage is the excessive yaw can reduce penetration and alter the projectile’s intended path, potentially diminishing its effectiveness.

VII.          Energy Transfer:

The concept refers to the kinetic energy that a projectile transfers to the target upon impact. The amount of energy transfer determines the extent of the damage.

Higher energy transfer typically leads, to more sever injuries, as more energy is deposited into the target tissues rather than being carries through the target such as over penetration.

 

VIII.          Over penetration:

Over penetration occurs when a projectile passes completely through the target, potentially exiting and posing a risk to anything beyond. Over penetration is generally undesirable as it indicates less energy has been transferred to the target, reducing stopping power.

Bullets designed to expand or fragment on impact help minimize over penetration.

 

  IX.          Wound Ballistics:

Wound ballistics is a subfield of terminal ballistics focused on the effects of projectiles on biological tissues. This includes studying how different types of bullets interact with human or animal tissue, the resulting injuries, and their lethality.

 

·        Tissue Composition: Different tissues such as muscle, bone, organs respond differently to penetration and energy transfer.

·        Wound Channels: The paths of the projectile and fragments through the body and the resulting trauma.

·        Shock Waves: The impact and propagation of shock waves from the bullet can cause additional tissue damage, beyond the direct physical path.

 

                    Hydrostatic Shock:

Hydrostatic shock refers to the idea that a projectile can cause a shock wave in the body’s fluids, leading to damage or incapacitation in tissues and organs distant from the bullets path. Particularly regarding whether it has significant effects in small caliber bullets. However, larger calibers and high velocity projectiles are more likely to induce hydrostatic shock.

 

XII.          Barrier Interaction:

Barrier interaction of projectiles refers to the study of how different types of barriers such as walls, armor, shields influence the behavior of projectiles upon impact. The intersection depends on several factors including the type of barrier, the material of the projectile, impact velocity, angle of impact, and the physical properties of both the projectile and the barrier.

Key factors include,

·        Projectile materials such as Hardness, Ductility and Brittleness and Mass and Density.

·        Barrier Materials such as Homogenous Materials, Composite Materials, Energy absorbing Materials.

·        Projectile Velocity such as Sub sonic, Super sonic and Hypervelocity.

·        Angle of Impact Such as perpendicular to impact, Oblique Impact, Glancing Blows.

·        Barrier Design and Configuration Such as, Monolithic Barriers, Layered or Composite Barriers, Reactive Armor and Spaced Armor.

·        Impact and Energy Dissipation Mechanisms such as Deformation, Cracking and Fracture, Spallation, Deflection.

 

XIII.          Bullet Design and Materials:

·        Jacketed Vs Non – Jacketed: Full metal jacket bullets tend to penetrate deeper, whereas non – jacketed or partially jacketed bullets like hollow points are designed to expand and transfer energy more effectively.

·        Lead Vs Steen Vs Polymer: Different materials affect how a bullet deforms, fragments, and transfers energy on impact.

 

XIV.          Incendiary and Explosive Effects:

Some projectiles are designed to ignite or explode upon impact, adding thermal or explosive damage to the mechanical effects of the projectile. Incendiary projectiles contain a chemical compound that ignites up on contact or detonation, spreading flames or heat over a target area. The primary aim is to cause fire or destroy material that are sensitive to heat, such as fuel, ammunition or electronics.

Some munitions are designed to combine both incendiary and explosive effects to maximize damage. These rounds typically incorporate both a high explosive charge and incendiary compounds to create a dual effect upon impact.

 

The Mechanisms of Combined Effects:

·        Initial Explosion: Upon impact, the explosive charge detonates, creating blast and fragmentation effects that damage or penetrate the target.

·        Secondary Incendiary Effect: Following the explosion, the incendiary compound ignites, causing fires or sustained heat damage to the target and its surroundings.

The examples of the combined Munitions like High Explosive Incendiary Rounds .

              The Mechanisms of Incendiary Effects:

·        Ignition of Flammable Materials: when an incendiary projectile strikes a target, the chemical payload ignites, often producing a high temperature flame capable of igniting surrounding materials. Targets like fuel tanks, munitions depots, or other flammable materials are particularly vulnerable.

·        Thermal Damage: The heat generated by incendiary rounds can damage or melt components, structures, or machinery. For example, a magnesium based incendiary round can reach temperatures of over 1650 degree Celsius, sufficient to penetrate light armor or cause significant internal damage to sensitive electronics.

·        Smoke and Heat Production: Incendiary rounds can also generate smoke and heat, creating additional secondary effects, such as obstructing visibility or forcing the evacuation of personnel form enclosed spaces. For example, Tracer Rounds, Phosphorus Rounds, Thermite Rounds.

 

XV.          Explosive Effects in Terminal Ballistics:

Explosive effects refer to the damage caused by a projectile through detonation, leading to a rapid release of energy that generates shock waves, shrapnel, and overpressure, causing destruction over a wide area. Explosive munitions are designed to maximize the destructive potential of the blast and fragmentation.

 

Mechanisms of Explosive Effects:

·        Blast Overpressure: The rapid release of energy from an explosive result in a high-pressure shock wave that travels outward form the detonation point. This over pressure can cause structural failures in buildings, destroy vehicles and incapacitate or kill personnel through direct physical trauma.

·        Fragmentation: Explosive munitions are often designed to produce shrapnel or fragments upon detonation. Therese fragments, often made of the casing or performed metallic components, travel at high velocities and cause severe injuries or penetrate armor.

·        Penetration and Breaching: Explosive effects can be focused to penetrate armor or fortifications, allowing the munition to breach protective barriers before detonating inside. Shaped charges, for instance, concentrate explosive energy in a directed jet to defeat armor.

·        Secondary Effects: Explosive can cause secondary effects such as fires, structural collapse, or the ignition or secondary explosives, amplifying the overall damage.

The example of the explosive munitions such as High Explosive Rounds, High Explosive Anti-Tank, Cluster Munitions.

 

It refers to the precise and intentional triggering of an explosive charge to achieve a specific outcome. This process involves managing the timing, location, and manner of the explosion to ensure that it meets predetermined objectives while minimizing unintended consequences. Controlled detonation is used in various applications.

·       Impact Fuse: Activated when the projectile or explosive device hits a target. This type of fuse ensures detonation upon impact.

·       Time Fuse: Set to trigger the explosion after a specific time period. This is often used in artillery shells or aerial bombs to detonate at a predetermined point during flight.

·       Proximity Fuse: Detonates when the explosive device come with in a certain distance of the target. It is used in some airburst munitions and anti-air craft projectiles.

·       Remote Detonators: Triggered by an external signal, such as radio control, allowing for detonation from a safe distance.