It's known that blaster bolts in Star Wars aren't instantaneous/speed-of-light - they are actually pretty slow (supposedly, slower than a high-velocity bullet).
Is there an official canon speed for how fast a blaster bolt travels?
I'm looking for one or both of:
Highest level canon calculations (presumably from G-canon, e.g. someone literally timing movie times and exact distances and calculating the speed; or word-of-god from Lucas or someone else involved in movie production).
and/or explicit mention of speed value in the non-movie canon (highest one available).