Airguns

Airguns are devices that propel projectiles using compressed air or gas rather than relying on combustion. They are widely used for sport shooting, target practice, pest control, and historically hunting in some regions. Modern airguns come in several mechanism families: spring-piston, pneumatic (including multi-pump), CO2, and pre-charged pneumatic (PCP). In a spring-piston gun, pulling the trigger releases a cocked spring that drives a piston forward, temporarily compressing the air in the barrel and pushing the pellet out. Pneumatic guns use stored compressed air released on firing; multi-pump models require manual pumping to raise the pressure. PCP guns carry high-pressure air in a built-in reservoir or detachable tank, enabling high velocity with each shot. CO2 guns use disposable carbon-dioxide cartridges and typically have lower velocity stability from temperature changes.

Pellets are typically .177 or .22 caliber, designed to be accurate with minimal recoil; BB guns fire steel BBs and are generally considered less powerful. Caliber choices and power vary widely, with some rifles capable of several dozen joules of energy, depending on the model and country.

Safety and legality: airguns should be treated as potentially dangerous; eye and face protection recommended; never point at people; secure storage. Regulations vary by country and subnational entity and may specify age requirements, licensing, background checks, or power limits. In some places, airguns are exempt from firearm licensing; in others, they are tightly regulated. History: devices using compressed air to fire projectiles date to the 16th–17th centuries; the modern airgun developed through the 19th and 20th centuries with standardized calibers and production models.