Sabot

A sabot (UK and Int.: /sæˈboʊ/, /ˈsæboʊ/), (US: /ˈseɪboʊ/) is a device used in a firearm or cannon to keep a projectile, such as a bullet, in the centre of the barrel when fired. It has a smaller diameter than the bore diameter of the weapon used.

Since a strong seal is needed to trap propellant gases behind the projectile, and keep the projectile centered in the barrel, something is needed to fill the undesirable but necessary gap between projectile and barrel, a space referred to as the windage, and this is the role of the sabot. Firing a small-size projectile wrapped in a sabot raises the muzzle velocity of the projectile. Made of some lightweight material (usually plastic in smallbore guns, and aluminium – and, in earlier times, wood or papier-mâché – in cannons), the sabot usually consists of several pieces held in place by the cartridge or a loose connection. When the projectile is fired, the sabot blocks the gas, and carries the projectile down the barrel. When the sabot reaches the end of the barrel, the shock of hitting still air pulls the parts of the sabot away from the projectile, allowing the projectile to continue in flight.

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