A rifle is a shoulder fired firearm that has rifled grooves in the barrel. These grooves make the bullet spin around an axis which stabilizes it during the flight. This makes the bullet more accurate and improves its range. Initially, rifles were known as “rifled guns”. However, the term “rifle” gradually replaced the earlier term in common usage. Rifles are commonly used in warfare, sports shooting and hunting.
A rifle bullet is propelled by using an explosive such as nitrocellulose. In the earlier days, black powder was the commonly used propellant. However, due to its disadvantages such as thick smoke and sooth, it was replaced with smokeless powder. Some rifles are also powered by compressed air. These rifles are generally used for pest control and for target practice.
There are many misnomers around the terms “gun” and “rifle”. In common language, the term gun refers to small weapons. However in actuality, the term “gun” can refer to any firearm–from a handheld revolver to a large sized artillery piece. Similarly, all firearms fired from the shoulder are commonly called “rifles”. However, this is not true. Shotguns do not have rifled barrels and so it would be incorrect to call a shotgun a rifle.
Traditionally, rifles were capable of firing only a single round at a time. However, modern rifles are capable of firing both in bursts and in fully-automatic mode. In fact, modern rifles overlap with submachine guns in many regards. Many machine guns designed for squad support are modified versions of assault rifles. For example, the Soviet RPK is a modified AK-47 with a heavier barrel and a bipod.
The rifle’s origin can be traced back to the original smoothbore musket. These muskets lacked range and accuracy. In addition, they were loaded from the muzzle.
In the subsequent years, it was discovered that cutting grooves into the barrel of the musket imparts spin to the projectile which stabilizes the bullet and increases the accuracy and range. It was not possible to load a rifle from the muzzle. The bullet would fit tightly into the barrel and because of the grooves, pushing it down the barrel was difficult. In addition, the bullet would also push dirt and soot deposited on the barrel from earlier shots and thus would jam the rifle.
Subsequently, a few developments were made to resolve the issue. One approach involved using a smaller ball which would expand upon firing. The second approach involved using a ball wrapped in a greased cloth. However, none of these were satisfactory and eventually breech-loaded rifles became with standard with armies across the globe.
The main differences between a machine gun and an assault rifle lie in the weight and ammunition capacity. Machine guns have heavier barrels and feed from a belt. The heavier barrel ensures that the weapon doesn’t get overheated and the belt ensures adequate firepower in the field. Assault rifles are designed to be fired by a single soldier. Machine guns may require a crew to operate.