Abstract: In a stock-piercing punch mechanism which includes a base having a punch-receiving bore, a punch having a stock-piercing tip positioned for reciprocal movement in said bore, and a cam trigger pivotably mounted on said base which is adapted to receive a stock-piercing force from a press ram or the like to cause the trigger to pivot and to transmit the force to the punch to move the punch out of the bore to pierce properly positioned stock, the improvement which comprises, a lubrication reservoir located in the base adjacent the punch so that as the punch moves in the bore it picks up and distributes the lubricant to reduce frictional wear of the punch and the bore. In the preferred embodiment the punch is removably attached to a punch plate positioned within the punch mechanism so that the punch can be readily removed and replaced with other punches having the same or different shape and size stock-piercing tips.