2. Jackson has a far pen value of 220 which is at 60 range, Pz 4 has frontal armor of 234 at vet 0. So at max range Jackson depends on RNG for a frontal armor hit.
That's a 94% chance to penetrate at max range up to a 100% chance at about range 40-45 (where it still outranges the P4). The RNG involved there is basically negligible and the Jackson certainly doesn't depend on it. The only noticeable RNG involved is accuracy, but that's still in favour of the Jackson with its higher moving accuracy.