A fastener driving tool with an improved nose chamber guide member is provided for driving fasteners of at least two different lengths. Multiple fasteners in a magazine are guided toward a driving bore to be driven by a driver blade. A nosepiece defines a passageway of the fasteners. The guide member is operatively connected to the nosepiece and is configured for transitioning between a first position and a second position relative to the nosepiece in a direction transverse to an operational flow direction of the fasteners. In the first position, the guide member is disposed to align with the driving bore for allowing driving of the fasteners having a first length. In the second position, the guide member is disposed out of alignment with respect to the driving bore for allowing driving of the fasteners having a second length, which is longer than the first length.