Deep in space a colony ship continues to accelerate unaware of the volley of railgun rounds hurtling towards it. As the light from the attack reaches the bridge the PDCs (Point defense cannons) are brought online and set to intercept the rounds. Unfortunately the ship is so massive and has accelerated so much that dodging or turning is not a option.
The 10 PDCs are 12 barreled caseless kinetic cannons firing 2mm composite slugs and nano disassembly rounds at a 12:1 ratio at a rate of 400 rounds per second and a muzzle velocity of 1000fps.
The railgun rounds are coming in at 2000fps every 20s for a total of 16 rounds. They are 2.5 pounds of titanium and mix of dense metals.
Assuming all the PDCs can be brought to bear can the cannons defend the ship? Defense means no rounds hit the ship.