Typology of firearms

The study of firearms and ballistics is a critical specialization within forensic science, playing a vital role in solving crimes involving the use of weaponry. This discipline ranges from detailed analysis of weapons to exhaustive examination of projectile trajectories and impacts. In this article, we will delve into the sub-specialties of ballistics — internal, external, and terminal — and explore the operating mechanisms of various types of firearms, providing a comprehensive view that is not only relevant for experts in the field but also fascinating for any reader interested in forensic science.

Ballistics and Its Divisions

Internal Ballistics

Internal ballistics studies the processes occurring inside the weapon from the moment the shooter presses the trigger to the bullet being expelled. This brief but complex interval is crucial for understanding how variations in weapon design can affect the trajectory and speed of the projectile.

External Ballistics

The phase of the projectile’s flight, from leaving the weapon to reaching its target, is the focus of external ballistics. Here, factors such as air resistance, gravity, and weather conditions play a significant role in the behavior of the projectile.

Terminal Ballistics

Also known as impact ballistics, this area focuses on what happens when the projectile impacts the target. Terminal ballistics is essential for understanding the lethal effects of different types of ammunition and for reconstructing shooting scenarios in criminal investigations.

Operating Mechanisms of Firearms

Firing Process

The firing of a firearm is a process that transforms the chemical energy of the propellant into kinetic energy that propels the bullet. From the percussion of the primer to the expulsion of the bullet, each stage within this process is critical for the effective functioning of the weapon.

Types of Loading and Reloading

Firearms are also classified according to their method of loading and reloading, from bolt mechanisms to recoil systems and gas-operated weapons. Each system has its peculiarities that can influence the choice of a weapon for different purposes, from hunting to personal security.

Types of Firearms and Their Regulations

Classification and Regulation

We will explore the various classifications of firearms according to laws, such as the UK’s Firearms Act of 1968, and how these categories affect both the availability and legal use of different types of weapons.

Diversity in Weapon Design

From revolvers to assault rifles and shotguns, each type of firearm has unique features that make them suitable for various applications. Additionally, we will discuss how modifications like barrel cutting can drastically alter the function and legality of a weapon.

Forensic Ballistics at the Crime Scene

Evidence Collection and Analysis

The collection of casings, bullets, and gunshot residue is essential for reconstructing a shooting event. We will analyze the techniques used to examine this evidence and how they can help establish the sequence of events in a crime.

Advanced Technology and Methodology

The adoption of advanced technologies, such as electron microscopy and ballistic databases, has revolutionized forensic ballistics, allowing faster and more accurate analyses than ever before.


The field of firearm research and ballistics is vast and complex, with significant implications for both public safety and criminal justice. By exploring the depths of this discipline, we not only expand our understanding of how weapons and projectiles operate but also enhance our ability to solve crimes and protect society. This article provides a comprehensive view that is not only informative but also engaging for anyone interested in forensic science or the technical aspects of firearms.

Firearms Act 1968
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Firearms & Ballistics. (s/f). Aboutforensics.co.uk. Recuperado el 9 de noviembre de 2021, de https://aboutforensics.co.uk/firearms-ballistics/