A surgical stapler, comprising: a channel configured to receive a staple cartridge comprising staples removably stored therein, wherein said channel comprises: a distal end; a proximal portion; and a stop; an anvil configured to deform staples ejected from the staple cartridge, wherein said anvil comprises a distal end and a proximal portion, wherein said proximal portion of said anvil is pivotably coupled to said proximal portion of said channel, and wherein said anvil is rotatable between an open position and a closed position; a closure tube movable between a first position and a second position, wherein said closure tube is configured to move said anvil between said open position and said closed position when said closure tube is moved between said first position and said second position, and wherein said closure tube comprises: a distal tube portion at least substantially encompassing said anvil and said channel; a first camming portion extending from said distal tube portion a first distance toward said distal end of said channel, wherein said first camming portion is configured to be at least partially positioned around said anvil when said closure tube is in said second position; and a second camming portion extending from said distal tube portion a second distance toward said distal end of said channel, wherein said first distance is larger than said second distance, wherein said second camming portion is configured to be at least partially positioned around said channel and adjacent to said stop when said closure tube is in said second position. a channel configured to receive a staple cartridge comprising staples removably stored therein, wherein said channel comprises: a distal end; a proximal portion; and a stop; a distal end; a proximal portion; and a stop; an anvil configured to deform staples ejected from the staple cartridge, wherein said anvil comprises a distal end and a proximal portion, wherein said proximal portion of said anvil is pivotably coupled to said proximal portion of said channel, and wherein said anvil is rotatable between an open position and a closed position; a closure tube movable between a first position and a second position, wherein said closure tube is configured to move said anvil between said open position and said closed position when said closure tube is moved between said first position and said second position, and wherein said closure tube comprises: a distal tube portion at least substantially encompassing said anvil and said channel; a first camming portion extending from said distal tube portion a first distance toward said distal end of said channel, wherein said first camming portion is configured to be at least partially positioned around said anvil when said closure tube is in said second position; and a second camming portion extending from said distal tube portion a second distance toward said distal end of said channel, wherein said first distance is larger than said second distance, wherein said second camming portion is configured to be at least partially positioned around said channel and adjacent to said stop when said closure tube is in said second position. a distal tube portion at least substantially encompassing said anvil and said channel; a first camming portion extending from said distal tube portion a first distance toward said distal end of said channel, wherein said first camming portion is configured to be at least partially positioned around said anvil when said closure tube is in said second position; and a second camming portion extending from said distal tube portion a second distance toward said distal end of said channel, wherein said first distance is larger than said second distance, wherein said second camming portion is configured to be at least partially positioned around said channel and adjacent to said stop when said closure tube is in said second position.