Efficient moves via spare chamber

A magazine-based data storage library is described that includes plurality of chambers each adapted to hold a magazine, that in turn, is adapted to hold a plurality of tape cartridges. The storage library further includes a tape drive adapted to read and write data to and from tape cartridges. The storage library further includes a vacant chamber that shifts from a first chamber when a recently used magazine is disposed therein to a second chamber when a new magazine is withdrawn there from. The recently used magazine most recently being withdrawn from a different chamber than the first chamber where it is later disposed.