A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and operated by an individual. The term is legally defined further in different countries.
A machine gun (MG) is a fully automatic and rifled firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles are typically designed more for firing short bursts rather than continuous firepower and are not considered true machine guns. Submachine guns fire handgun cartridges rather than rifle cartridges, therefore they are not considered machine guns, while automatic firearms of 20 mm (0.79 in) caliber or more are classified as autocannons rather than machine guns.
In firearm designs, the term single-shot refers to guns that can hold only a single round of ammunition inside and thus must be reloaded manually after every shot. Compared to multi-shot repeating firearms ("repeaters"), single-shot designs have no moving parts other than the trigger, hammer/firing pin or frizzen, and therefore do not need a sizable receiver behind the barrel to accommodate a moving action, making them far less complex and more robust than revolvers or magazine/belt-fed firearms, but also with much slower rates of fire.
The percussion cap, percussion primer, or caplock, introduced in the early 1820s, is a type of single-use percussion ignition device for muzzle loader firearm locks enabling them to fire reliably in any weather condition. Its invention gave rise to the caplock mechanism or percussion lock system which used percussion caps struck by the hammer to set off the gunpowder charge in rifles and cap and ball firearms. Any firearm using a caplock mechanism is a percussion gun. Any long gun with a cap-lock mechanism and rifled barrel is a percussion rifle. Cap and ball describes cap-lock firearms discharging a single bore-diameter spherical bullet with each shot.
In firearms terminology, an action is the functional mechanism of a breech-loading firearm that handles the ammunition cartridges, or the method by which that mechanism works. Actions are technically not present on muzzleloaders, as all those are single-shot firearms with a closed off breech with the powder and projectile manually loaded from the muzzle. Instead, the muzzleloader ignition mechanism is referred to as the lock.
Flintlock is a general term for any firearm that uses a flint-striking ignition mechanism, the first of which appeared in Western Europe in the early 16th century. The term may also apply to a particular form of the mechanism itself, also known as the true flintlock, that was introduced in the early 17th century, and gradually replaced earlier firearm-ignition technologies, such as the matchlock, the wheellock, and the earlier flintlock mechanisms such as the snaplock and snaphaunce.
A wheellock, wheel-lock, or wheel lock is a friction-wheel mechanism which creates a spark that causes a firearm to fire. It was the next major development in firearms technology after the matchlock, and the first self-igniting firearm. Its name is from its rotating steel wheel to provide ignition. Developed in Europe around 1500, it was used alongside the matchlock, the snaplock, the snaphance, and the flintlock.
A breechloader is a firearm in which the user loads the ammunition from the breech end of the barrel, as opposed to a muzzleloader, in which the user loads the ammunition from the (muzzle) end of the barrel.
A repeating rifle is a single-barreled rifle capable of repeated discharges between each ammunition reload. This is typically achieved by having multiple cartridges stored in a magazine and then fed individually into the chamber by a reciprocating bolt, via either a manual or automatic action mechanism, while the act of chambering the round typically also recocks the hammer/striker for the following shot. In common usage, the term "repeating rifle" most often refers specifically to manual repeating rifles, as opposed to self-loading rifles, which use the recoil, gas, or blowback of the previous shot to cycle the action and load the next round, even though all self-loading firearms are technically a subcategory of repeating firearms.
A breechblock is the part of the firearm action that closes the breech of a breech loading weapon before or at the moment of firing. It seals the breech and contains the pressure generated by the ignited propellant. Retracting the breechblock allows the chamber to be loaded with a cartridge.
The lock of a firearm is the mechanism used to initiate firing. It is generally used as a historical term, referring to such mechanisms used in muzzle-loading and early breech-loading firearms, as modern firearms uniformly fire by use of a firing pin to strike the rear of a cartridge. Side-lock refers to the type of construction, in which the individual components of the mechanism are mounted either side of a single plate. The assembly is then mounted to the stock on the side of the firearm. In modern firearm designs, the mechanism to initiate firing is generally constructed within the frame or receiver of the firearm and is referred to as the firing or trigger mechanism.
The M1819 Hall rifle was a single-shot breech-loading rifle designed by John Hancock Hall, patented on May 21, 1811, and adopted by the U.S. Army in 1819. It was preceded by the Harpers Ferry M1803. It used a pivoting chamber breech design and was made with either flintlock or percussion cap ignition systems. The years of production were from the 1820s to the 1840s at the Harpers Ferry Arsenal. This was the first breech-loading rifle to be adopted in large numbers by any nation's army, but not the first breech-loading military rifle – the Ferguson rifle was used briefly by the British Army in the American Revolutionary War. The Hall rifle remained overshadowed by common muskets and muzzleloading rifles which were still prevalent until the Civil War. The early flintlocks were mostly converted to percussion ignition.
The Puckle gun was a primitive crew-served, manually-operated flintlock revolver patented in 1718 by James Puckle (1667–1724), a British inventor, lawyer and writer. It was one of the earliest weapons to be referred to as a "machine gun", being called such in a 1722 shipping manifest, though its operation does not match the modern use of the term. It was never used during any combat operation or war. Production was highly limited and may have been as few as two guns.
A handgun is a firearm designed to be usable with only one hand. It is distinguished from a long barreled gun which needs to be held by both hands and braced against the shoulder. Handguns have shorter effective ranges compared to long guns, and are much harder to shoot accurately. While most early handguns are single-shot pistols, the two most common types of handguns used in modern times are revolvers and semi-automatic pistols, although other handguns such as derringers and machine pistols also see infrequent usage.
The following are terms related to firearms and ammunition topics.
The Belton flintlock was a repeating flintlock design using superposed loads, conceived by Philadelphia, Pennsylvania, resident Joseph Belton some time prior to 1777. The musket design was offered by Belton to the newly formed Continental Congress in 1777. Belton wrote that the musket could fire eight rounds with one loading, and that he could support his claims "by experimental proof." Belton failed to sell the musket to Congress, and later was unable to sell the design to the British Army a year after the American Revolution. There are no records that indicate that the gun was ever supplied, and it is uncertain if or how exactly the Belton improvement operated.
The Cookson flintlock rifle, a lever-action breech-loading repeater, also known as the Cookson gun, is one of many similar designs to appear beginning in the 17th century. The Victoria & Albert Museum in London has a Cookson Gun, dating to 1690. According to the museum, John Cookson made several repeating guns based on this system. He signed one 'Fecit Londini', which suggests he was a London maker. Another John Cookson, who was also a gunmaker, is known to have worked in America. He is recorded in Boston, Massachusetts between 1701 and 1762. In 1756 he advertised repeating firearms firing nine shots in the local paper, the Boston Gazette. It is probable that he was related to the John Cookson who worked in London.
The Kalthoffs were a prominent Danish-German family of gunsmiths during the 17th century, best known for the Kalthoff repeater — a rapid fire flintlock repeating rifle that could reach a rate of fire of 20–30 rounds/minute. Signed specimens of their guns can be found kept in the Windsor Castle, the Danish War Museum, the Swedish Royal Armoury and the Kremlin Armoury collections.
Armand Barnevelt was a Dutch gunsmith. He is known for his weapons made in England, which he immigrated to around 1642. He is mostly known as Harman Barnes.
A repeating firearm or repeater is any firearm that is capable of being fired repeatedly before having to be manually reloaded with new ammunition from the magazine.
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