A touch hole, also called a vent, is a small hole at the rear (breech) portion of the

barrel A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, ...

of a

muzzleloading Muzzleloading is the shooting sport of firing muzzleloading guns. Muzzleloading guns, both antique and reproduction, are used for target shooting, hunting, historical re-enactment and historical research. The sport originated in the United States ...

gun or

cannon A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...

. The hole provides external access of an

ignition Ignition may refer to: Science and technology * Firelighting, the human act of creating a fire for warmth, cooking and other uses * Combustion, an exothermic chemical reaction between a fuel and an oxidant * Fusion ignition, the point at which a ...

spark into the breech chamber of the barrel (where the combustion of the

propellant A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the ...

occurs), either with a slow match (

matchlock A matchlock or firelock is a historical type of firearm wherein the gunpowder is ignited by a burning piece of rope that is touched to the gunpowder by a mechanism that the musketeer activates by pulling a lever or trigger with his finger. Befor ...

), a

linstock A linstock (also called a lintstock) is a staff with a fork at one end to hold a lighted slow match. The name was adapted from the Dutch ''lontstok'', "match stick". Linstocks were used for discharging cannons in the early days of artillery; th ...

or a flash pan ignited by some type of

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), lust ...

- ( wheellock) or

flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Flint was widely used historically to make stone tools and start ...

-based gunlock (

snaplock A snaplock is a type of lock for firing a gun or is a gun fired by such a lock. A snaplock ignites the (usually muzzle-loading) weapon's propellant by means of sparks produced when a spring-powered cock strikes a flint down on to a piece of hard ...

, snaphaunce and

flintlock 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 know ...

), which will initiate the

combustion Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combus ...

of the main

gunpowder Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate (saltpeter). T ...

charge. Without touch hole, it would be nearly impossible to ignite the powder because the only otherwise access into the barrel is from the front via the muzzle, which is obturated by the

projectile A projectile is an object that is propelled by the application of an external force and then moves freely under the influence of gravity and air resistance. Although any objects in motion through space are projectiles, they are commonly found i ...

. In the later

caplock The percussion cap or percussion primer, 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. This crucial invention gave rise ...

firearms, the ignition sparks are generated by a shock-sensitive

percussion cap The percussion cap or percussion primer, 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. This crucial invention gave rise ...

placed over a conical "nipple", which has a hollow conduit known as the flash channel, that leads into the barrel and serves the same function as the touch hole. In modern

breechloading A breechloader is a firearm in which the user loads the ammunition ( cartridge or shell) via the rear (breech) end of its barrel, as opposed to a muzzleloader, which loads ammunition via the front ( muzzle). Modern firearms are generally bre ...

firearms, the propellant charge is packaged inside a cartridge, which has a modified percussion cap (

primer Primer may refer to: Arts, entertainment, and media Films * ''Primer'' (film), a 2004 feature film written and directed by Shane Carruth * ''Primer'' (video), a documentary about the funk band Living Colour Literature * Primer (textbook), a te ...

) seated in a cavity at the back end of the cartridge case. Between the primer pocket and the case chamber are one or more apertures known as flash holes, which serves functionally as a touch hole ''inside'' the cartridge. In

artillery Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during si ...

, priming powder, a

fuse Fuse or FUSE may refer to: Devices * Fuse (electrical), a device used in electrical systems to protect against excessive current ** Fuse (automotive), a class of fuses for vehicles * Fuse (hydraulic), a device used in hydraulic systems to protect ...

, squib, or

friction igniter Tubes and primers are used to ignite the propellant in projectile weapons. In ancient times various devices were adopted to ignite the charge. Small guns were fired by priming powder poured down the touch hole (or vent) and ignited by glowing em ...

is inserted into the touch hole to ensure ignition of the charge. The ignition might be achieved via striking or electrically.

Spiking the guns

''Spiking a gun'' was a method of temporarily disabling a

by hammering a barbed steel spike into the touch hole; this could be removed only with great difficulty. If a special spike was unavailable, spiking could be done by driving a

bayonet A bayonet (from French ) is a knife, dagger, sword, or spike-shaped weapon designed to fit on the end of the muzzle of a rifle, musket or similar firearm, allowing it to be used as a spear-like weapon.Brayley, Martin, ''Bayonets: An Illustr ...

into the touch-hole and breaking it off, to leave the blade's tip embedded. Guns could also be rendered useless by burning their wooden

carriage A carriage is a private four-wheeled vehicle for people and is most commonly horse-drawn. Second-hand private carriages were common public transport, the equivalent of modern cars used as taxis. Carriage suspensions are by leather strapping ...

s or blowing off their

trunnion A trunnion (from Old French "''trognon''", trunk) is a cylindrical protrusion used as a mounting or pivoting point. First associated with cannons, they are an important military development. Alternatively, a trunnion is a shaft that positions a ...

s. Count Friedrich Wilhelm von Bismarck, in his ''Lectures on the Tactics of Cavalry'', recommended that every cavalry soldier carry the equipment needed to spike guns if an encounter with enemy artillery was expected. If a cannon was in danger of being captured by the enemy, its crew would spike the gun to prevent it from being used against them. Captured guns would be spiked if they could not be hauled away and the gun's recapture seemed likely. Covert missions to spike the enemy's guns could also be done to prevent counterattacks and protect ships during withdrawal, as in the case of the ''Rangers attack on Whitehaven during the

American Revolutionary War The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, was a major war of the American Revolution. Widely considered as the war that secured the independence of t ...

References

{{reflist Firearm components Articles containing video clips