A firing assembly comprising a stationary housing including a U-shaped frame having a bottom wall and a pair of sidewalls, the stationary housing having a proximal portion and a distal portion, a slide block supported in the proximal portion of the stationary housing, a guide block supported in the distal portion of the stationary housing, the guide block defining a plurality of slots, a knife actuating bar having a proximal portion secured to the slide block and a distal portion positioned within one of the plurality of slots, a cam bar having a proximal portion secured to the slide block and a distal portion extending through one of the plurality of slots, and a pivotal locking member pivotally secured within the proximal portion of the stationary housing, the pivotal locking member including a latch portion and being pivotal from an unlatched position to a latched position.
