Take the tour ×  After reviewing my math, it turns out I had
made a mistake in my calculations and was off by a couple
factors. In an effort to make this question worthwhile, I am
still interested in what type of device can perform very
specific calculations at at high seeds and low latencies.
share|improve this question The speed and size of the projectile
are probably pretty important to this task. The accuracy
required for detection can create a completely different
solution space. –  Kortuk Jun 9 '12 at 14:07 I think you may
have better luck measuring the speed at a distance from the
target, and trying to derive the impact speed from it. – 
clabacchio Jun 9 '12 at 14:17 @clabacchio, it might be a really
tiny particle on a straight path and a laser would work
perfectly. Without details whom can know. –  Kortuk Jun 9 '12 at
14:24 What sensors are you going to find that can react in a
small fraction of 10 ns to allow calcluations to be performed
elsewhere? Keep in mind that 10 ns is about 5 feet of wire at