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Barrel rifling was invented in Augsburg, Germany at the end of the fifteenth century. In 1520 August Kotter, an armourer of Nuremberg, Germany improved upon this work. Though true rifling dates from the mid-16th century, it did not become commonplace until the nineteenth century.espite differences in form, the common goal of rifling is to deliver the projectile accurately to the target. In addition to imparting the spin to the bullet, the barrel must hold the projectile securely and concentrically as it travels down the barrel. This requires that the rifling meet a number of tasks:
'Rifling' is grooves in a barrel which grip and spin the projectile, like this cut-away of the venerable L7 105mm shows: This is the classic rifling method, called 'land and groove'.However, there are different types of rifling, including one called 'polygonal rifling', which has undulations in the inside of the barrel with hills and valleys, instead of sharp-edged lands and grooves:Illustrating the differences with a schematic:n small arms bullets, where you actually deform the entire projectile, polygonal rifling is supposed to give a sightly better gas seal and slightly lower friction. For large-caliber systems, the driving band system offers less deformation of material, and therefore less wear.