cross section of a muzzle loading

bore

Hollow part of the muzzle loading that guided the projectile.

wad

Double pad that kept the projectile in place and transmitted the thrust explosion.

powder chamber

Part containing the gunpowder charge; it was positioned behind the projectile.

vent

Opening in the barrel for igniting the powder charge.

shot

Solid spherical projectile that was loaded into cannons; they were first made of stone, then of cast iron from the 16th century.