I agree with the latest range regarding snipe, as I was about to point the ranges being closest to closest.
I'll toss in my view on FC and Howl
FC: Doesn't work, because the Snipe specifies that AS armament to use. Like counter on a Raider, it still goes by what the keyword says, instead of any AS dice.
To use an example: FC would be equivalent to adding a 3rd black (for the sake of argument) die to the Raider 1, and adding QLT to it. Which gives it counter 1. If attacked, it still only gets that counter 1, with a blue die regardless of it's normal anti-squadron armament.
Howlrunner: Does work, because it's a dice modification after the fact.