.220 Rook  The .220 Rook, also known as the .220 Long Centrefire, is an obsolete British centerfire rifle cartridge. The .220 Rook is a rimmed cartridge originally designed for use in rook rifles, it was designed and produced in Britain in the 1880s. It is believed to be an early centrefire version of the .22 Long Rifle rimfire cartridge. The .220 Rook fired a bullet of weight driven by of black powder, it was designed for hunting small game and target shooting, although many considered it too small for practical hunting purposes.