There is little doubt Whitworth pioneered the system later called QF (Quick Fire) for when he used the gun as a breech-loader he enclosed the propellant charge in a sheet iron cartridge case shaped to fit the hexagonal bore, thus effectively providing obturation. After firing it was extracted with a special tool. If used as a muzzle-loader the charge was enclosed in a cloth bag as with other ML guns. Projectiles were precisely shaped to fit the bore with negligible windage; a wad in rear ensured complete sealing. Whitworth pioneered the use of streamlined shot and shell, and demonstrated the significant increase in range obtainable.