A tool assembly for a surgical stapling instrument includes anvil andcartridgeassemblies movable between open and closed positions. The cartridge assemblyincludes acartridge body defining a tissue contact surface and rows of staples. Thecartridge bodydefines a first firing channel associated with a first row of staples and asecond firing channelassociated with a second row of staples. A firing cam is positioned within thefirst firingchannel and translates therethrough during a first axial translation to firethe first row ofstaples. The first firing cam is biased to move into the second firing channelupon retractionafter the first axial translation such that the first firing cam translatesthrough the secondfiring channel upon a second axial translation to fire the second row ofstaples.
