A carbine and rifle are two types of firearms that can easily be mistaken for one another because their appearance is quite similar. In fact, the term carbine has historically been used to describe a shorter version of an existing rifle. However, in modern times there are several differences between the two that become quite apparent quickly, and are especially notable upon firing both.
Despite appearing to be very similar, there is typically one difference in their appearance, the length. A carbine is typically shorter than a rifle. This means that it is also lighter which is why some would prefer to use a carbine when necessary rather than a rifle, but the shorter length does not necessarily mean that it is more accurate or effective than the rifle. They typically are equivalents when both are operated properly. However, the length difference does impact the amount of power that is behind a bullet that is fired. Since a rifle is longer, the expanding air has more time to produce energy before the bullet exits the barrel, which means that the impact of the projectile will be harder and the individual firing may actually feel the difference in power when firing both a carbine and a rifle.[i]
- Barrel Surface
The barrel surface of the carbine and rifle used to be similar and both were smooth internally. However, today it is a key difference between them in that the barrel of a rifle is typically grooved, or ‘rifled.’ Since the grooves cause a unique spin on the bullet when it leaves the barrel, it will typically become more stable as it moves through the air. This is thought to improve the accuracy is it travels toward its target. The bullets shot from a carbine are slower and could potentially be less accurate for individuals who are not familiar to operating the carbine. However, the difference in accuracy attributed to the barrel differences is usually quite small and could be overcome with experience in operating both types of firearms.[ii]
Rifles and carbines both have had many different uses within the military and in hunting game throughout history. Today, rifles are the most common firearm used for general hunting purposes, excluding bird hunting which favors shotguns. Rifles that were derived from military designs have always been popular with civilian shooters.[iii] The smaller size and lighter weight of the carbine make it more practical for modern military purposes, especially in engagements that happen in close proximity, such as urban warfare. In the late 20th century, the US military adopted the M4 carbine, a relative of the M16, for military applications. The Army quickly began carrying this carbine, while the Marine Corps opted to retain a M16A4 rifle, although some who had restricted mobility, such as vehicle drivers, or those with a greater need for mobility, like squad leaders, were also issued an M4 carbine. The Marine Corp did update this policy in 2015 and also approved standard issue of the M4 carbine to front-line Marines rather than the M16A4 rifle. They are also issued to high-mobility troops, such as special-operations soldiers and paratroopers as well as other mounted, artillery, logistics or other non-infantry personnel that do not require a full size rifle.[iv]
Rifles and carbines have a lot of overlap with the caliber of bullet that can be used with each. The caliber refers to the ammunition’s width. But there are some different trends for each type of firearm. Rifles have a very wide range of calibers, starting at the .17 for varmint and commonly going to the .80, which would be used for the largest anti-tank rifle. There are some that are larger, but generally they are rare. During World War II, the .30 caliber became popular with the rifle,[v] and even today the range from .30-.39 is where you see the most options. With carbines, the most common types of calibers are going to be the same as what is found with a pistol-caliber. The simple reason that pistol-calibers became common is because in the early days of the carbine’s existence it was commonly carried as a companion to a revolver. In the modern era, one example of a very common combination would be the Ruger Model 44 and the Ruger Deerfield Carbine. As both would use the .44 Magnum ammunition. The caliber range for these types of carbines typically ranges from .22 to .44.
The history of the rifle pre-dates that of the carbine and it is difficult to trace its exact origin, but it’s beginnings seem to have occurred in 15th century Europe, with true rifling, or the boring of grooves into the barrel of a musket, occurring in the mid-15th century. Rifles themselves developed over the next couple centuries and made a huge advancement in accuracy when elongated bullets were developed to replace the ball-shaped ammunition that was previously used. Rifles became popular for military use in the 19th century and have since become primarily used for hunting and gaming uses.[vi] In contrast to the rifle, the carbine became popular for warfare much earlier due to the fact that it was lighter and shorter which made it much easier to transport by infantry. Throughout different wars, including the Civil War, World War I and II, the Vietnam war and with current modern military campaigns, variations of the carbine have always been popular. Today, it is favored by special forces within the military and for certain application. Certain variations of carbines today are banned or face additional taxation if purchased for non-military applications.[vii]