Assault rifles have come a long way from the level of standard-issue gun—they are today the classic firearms of the modern soldier. They transformed warfare, offering the perfect blend of firepower, adaptability, and simplicity that no earlier gun could offer. From their initial introduction in World War II to the high-tech versions present today, assault rifles have continued to evolve in response to the changing demands of warfare.
What characterizes an assault rifle is the ability to switch between firing modes—full-auto, semi-auto, or burst fire—giving soldiers versatility in battle. They shoot intermediate cartridges, more potent than a pistol cartridge but not as complicated to handle as a standard rifle cartridge. Coupled with detachable magazines, light weight, and operation by a single man, these attributes suit assault rifles well for mobile warfare in countless varied environments.
The concept first arose during World War II with Germany’s Sturmgewehr 44 (StG 44). It introduced the key features that would define the assault rifle: select-fire capability, an intermediate caliber, and a compact firearm to enable easier handling. After the war, the Soviet Union developed further from the concept with the AK-47, created by Mikhail Kalashnikov. Praised for its crudeness, simplicity, and mass-producibility, the AK-47 was the standard of armies everywhere and a typical choice for irregular combat forces.
The United States initially went another way with the M14, a 7.62x51mm NATO full-power rifle designed to replace several older guns. While effective as a concept, it was too heavy and difficult to handle in automatic fire. Vietnamese experience, particularly jungle warfare, demonstrated the need for a more manageable and lighter gun.
The M16, with its smaller 5.56x45mm cartridge, allowed soldiers to carry more ammunition without losing accuracy. There developed the M4 Carbine was developed, which was a folding-stock shortened version of the M16, better adapted to close combat.
At the same time, Russia further developed the AK platform. The AK-12, the most recent in the Kalashnikov series, features contemporary accessories such as rails, enhanced ergonomics, and ambidextrous controls, yet retains the rugged simplicity that has characterized the series for decades.
Its design tolerances and gas piston system provide it with the capability to function reliably in harsh environments, from mud to snow, prioritizing practical durability over manufacturing standards.
As fighting moved onto the streets, shorter-barrelled assault rifles became more popular. The AKS-74UN and SIG Sauer MCX Rattler are examples of the direction. They are compact, foldable, and highly modular, ideal for special forces, vehicle crews, or urban close-quarters combat.
The AKS-74UN measures only 19 inches with its stock folded, while the MCX Rattler can change calibers without diminishing its performance, which indicates the greater call for flexibility and quickness in tight places.
Assault rifles move forward into the future. The U.S. Army will start fielding the XM7 under the Next Generation Squad Weapon program. From SIG Sauer, the XM7 uses a new 6.8x51mm cartridge that offers greater effective range and penetration against modern body armor.
The weapon also features new ergonomics, modularity, and high-end optic compatibility. All of this is part of a broader trend in infantry rifles: the incorporation of new materials, smarter ammunition, and electronics to fit the requirements of modern and future battlefields.