shotgun
Shoulder weapon made up of a long barrel attached to a frame; it uses cartridges loaded with 24 g of lead having a diameter no greater than 2.5 mm.
cheek piece 
Movable and adjustable part against which the shooter can rest his cheek when shouldering the weapon.
cartridges 
Ammunition consisting of a projectile (ball or lead), an explosive charge (gunpowder) and a primer collected inside a casing.
plastic case 
Cylindrical cover that contains the cartridge’s gunpowder and projectile.