Null-space weapons vs. temporal weapon

[Yimboli]

I was wondering if the null-space cannon's damage is any different than the temporal weapon that skips shields and armor. THe damage type is listed as the same: "Skips shields and armor" - but the null-space cannon does more damage and goes like twice as far, so I figure that there simply must be some difference, otherwise there would be no point to the temporal weapon!

Thanks!
-Timbo