Assault weapon is a term which originated in the United States to define some types of firearms. The definition varies among regulating jurisdictions, but usually includes semi-automatic firearms with a detachable magazine and a pistol grip, and sometimes other features such as a flash suppressor or barrel shroud. Some firearms are specified by name. At the time that the nowdefunct Federal Assault Weapons Ban passed in 1994, the US Justice Department said, “In general, assault weapons are semiautomatic firearms with a large magazine of ammunition that were designed and configured for rapid fire and combat use.” The name assault rifle seems to have also evolved from this term. This refers to military rifles that can fire in automatic and/or burst mode.

Common attributes of assault weapons as accepted in various legislations in the United States include:

• Semi-automatic firearm (now capable of firing in an automatic mode) and capable of accepting a detachable magazine
• Folding or telescoping (collapsible) stock, which reduces the overall length of the firearm.
• A pistol grip that protrudes conspicuously beneath the action of the weapon
• Bayonet lug, which allows the mounting of a bayonet
• Threaded barrel, which can accept devices such as a flash suppressor, suppressor, compensator or muzzle brake.
• Grenade launcher
• Barrel shroud, which prevents burning of shooter’s arm or hand as a safety device.
• Night firing aids such as NVDs or thermal imaging devices.

The modern assault rifle is an appropriate example of an ‘assault weapon’ as defined originally but currently with new technologies the assault weapon such as an assault rifle has become far more lethal than what was imagined earlier. Some of the new technologies in use in assault weapons such as assault rifles are briefly given in the succeeding paragraphs.

Bullpup Design and Accuracy

The accuracy of a weapon is dependent on the length of the barrel among other factors. When you go to a bullpup design (developed in 1950s), because you move the magazine behind the pistol grip, you can move the chamber of the barrel back where the magazine is. The overall length of the rifle is shorter, however the length of the barrel can remain long for accuracy purposes. So the bullpup layout attempts to address the mobility versus accuracy issue. If you have a shorter weapon, it should help you move through tight spaces that much easier. The question that arises is, can the person shoot more accurately with it? And can they shoot more quickly?

Accuracy is dependent upon other factors as well. While training certainly has an important role to play, so do design and optical technologies.

Material Used

Dr Franklin Wong of Defence Research and Development Canada (DRDC) says: “The bullet has to achieve a certain stability as it leaves the barrel so that it flies straight,” he explained. “Shooting a bullet is sort of like an internal combustion engine. There’s a big explosion with a flow of hot gases. Every time you shoot a round it’s like hitting the barrel with a hammer with each explosion. That’s where inaccuracies come in…..It’s very hard to predict where your bullets are going to go if your barrel, due to material used and the mechanical design, is always changing where it’s deflecting. One of the goals for our weapon studies is to understand what materials and mechanical designs give consistent barrel dynamics,” he concluded.

Combat Sights

Combat sights allow shooters to compensate if the barrel deflection behaviour remains consistent, in addition to allowing the user to more quickly identify and engage targets. These sights fall into one of two categories: direct optics and electro-optics.

While direct optic sights can improve reaction time in daytime conditions by providing clear, bright images, electro-optical models may have even greater potential. Dr Wong explains: “Once you have a digital image, this is where you can bring in visible and thermal cameras with image processing and then have algorithms that will help, for example, fuse the images from the visible and thermal cameras or automatically detect threats. And then once, for example, an algorithm has detected a threat, it will present that information along with a fused image in some form to the soldier on a micro display. So we see that there are potential gains to be made in the reduction of time needed to detect, recognize and identify threats with this technology.”

Night Vision

It is vital requirement for the modern battlefield where operations will be fought by day as well as by night. The two types of night sights available are basically the Night Vision Devices (NVDs) which are based on image intensification principle and the thermal imaging sight.

An NVD, also known as a night optical/observation device (NOD), is an optoelectronic device that allows images to be produced in levels of light approaching total darkness. The image produced is typically monochrome, e.g. shades of green. NVDs are most often used by the military and law enforcement agencies, but are available to civilian users. The term usually refers to a complete unit, including an image intensifier tube, a protective and generally water-resistant housing, and some type of mounting system. An NVD may have an IR illuminator, making it an active as opposed to passive night vision device.

Thermal rifle scopes offer the flexibility of daytime and night time use, but they also deliver in weather conditions when other optical devices simply fail. Fog is one such example. Like all other thermal imaging devices, thermal riflescopes read off thermal signatures of all objects and present the user with an image showing a gradient map of the heat signatures. Today there are 2 in 1 thermal units, designed to be used as either scanning monoculars or front riflescope attachments.

Some Modern Assault Rifles

In order to understand the attributes of assault weapons let us take the example of some modern assault rifles.

F90 Assault Rifle. The F90 which is a lightweight assault rifle manufactured by Thales Australia to provide soldiers with increased firepower in the battlefield. The new generation F90 is an evolution of the Austeyr F88 assault rifle, which is operational in more than 30 countries, including Australia and New Zealand. The rifle has five variants, namely F90, F90(G) (grenade launcher variant), F90M (Marksman variant with a longer barrel), F90M(G) and F90CQB (close quarters battle-a carbine). F90’s bullpup design and open architecture allow it to be configured for a wide range of mission profiles. The rifle has an overall length of 700mm and a weight of 3.25 kg. It is equipped with a 407mm long fixed and lighter barrel. It is provided with cold hammer forged chrome lined barrels in all configurations for improved barrel life and precision. An enhanced grenade launcher quadrant sight delivers rapid target acquisition and fast reaction times. It is compatible with night vision goggles and can support operations during low-light/night conditions.

M16A2/A4 Assault Rifle. The M16 series assault rifles are weapons of choice of the US Armed Forces, and are chambered for NAT O 5.56 x 45mm ammunition. More than eight million M16 rifles have been sold to 15 NAT O states and over 80 countries. The M16 variants are in service with the US Army, Navy and Marine Corps, the latest among them is the M16A4 which was inducted during Operation Iraqi Freedom. The shortened version of the M16A2, M4 Carbine supplements the M16 that is in use with most of the US Army combat units. The M16A4 weighs 3.26 kg and integrates a removable carrying handle and rail mounting for installing optical sights and other auxiliary devices. The rifle has a rate of fire of 700 to 950 rounds and effective range of 600 metres.

Russian AK-12. The Russian Army is inducting modified version of new Kalashnikov AK-12 assault rifle along with several other small arms into operational service.

An upgraded variant of the Russian Army’s Soviet-era 5.45mm calibre AK-74 Kalashnikov series, AK-12 is capable of firing foreign-standard barrel-mounted grenades in three different modes, including single shot, three-shot burst and automatic fire. Rolled out by its manufacturer, Izhmash in January 2012, the rifle retains almost all the AK-74’s features and overall layout, with enhanced technology and features a folding stock, height-adjustable heelpiece, as well as Picatinny rails to support attachment of optical and night-sights, grenade launchers, target indicators and other special equipment. Configurable for cartridges varying from 5.45mm x 39mm to 7.62mm x 51mm Nato standard, the rifle is also designed to serve as a basic platform for development of AK-12U carbine, PPK-12 submachine gun, SVK-12 sniper rifle, RPK-12 light machine gun and several other export versions.

QBZ-95. The QBZ-95/Type-95 is the standard issue assault rifle of the Chinese People’s Liberation Army (PLA) and is also exported to Cambodia, Myanmar, Pakistan, Sri Lanka and Sudan. It is chambered for a Chinese made DBP87 5.8 x 42mm rounds. The QBZ-95 is a gas operated, automatic rifle incorporating bullpup design. It is fed by 30 round magazine and can fire 650 rounds per minute to an effective range of 600 metres. The rifle features hooded front sight post and rear sight base, while its rail mounting points allow the mounting of optical or night vision scopes. It can be mounted with an underbarrel grenade launcher or a bayonet.

G3A3 Automatic Rifle. The G3A3 automatic rifle, derived from Heckler & Koch G3, is produced by Pakistan Ordnance Factories for the Pakistan Army. The modern rifle is chambered for 7.62x51mm NATO standard rounds. The rifle fires ammunition in semi automatic and fully automatic modes and can be fed through 20-round box magazine. The rifle weighs 4.4 kg and can be mounted with fixed hooded front post and adjustable rotary rear sight. The cyclic rate of fire of the G3A3 is 500 to 600 rounds per minute and the effective range is 400 metres.