The operation of a shotgun involves a complex interplay of mechanical and chemical processes. When the trigger is pulled, a firing pin strikes the primer of a shotshell. This ignites the primer, which in turn ignites the gunpowder within the shell. The rapidly expanding gas generated by the burning gunpowder propels a wad containing numerous small pellets, or shot, down the barrel. The constriction at the end of the barrel, known as the choke, influences the spread of the shot as it leaves the muzzle.
Understanding the mechanics of a shotgun is essential for safe handling and effective use. A firm grasp of these principles allows for informed decisions regarding ammunition selection, aiming techniques, and overall firearm maintenance. Historically, the development of the shotgun has been driven by advancements in metallurgy, chemistry, and engineering. These improvements have led to more efficient, reliable, and safer firearms.