What is weight of stock 340 piston

The heavy rods are around 758.... I got an average of 760.6 grams on a set of 340 rods within the last month. Light rods are 726 grams nominal. Not sure where I picked up the 719 grams but the old ones that I have are close. (They are so corroded from being left in a wet box by the PO that I can't take their weight as gospel. I just got them for the rods.)