If I measure Range for Snapshot and I'm in Range 1, am I now stuck with Snapshot or can I not and wait if another person is gonna come into range?

Measuring for Snap Shot can be done any time a ship executes a maneuver. You don't have to declare the target and proceed with the attack. Attacking is optional.

5 minutes ago, jmswood said:

Measuring for Snap Shot can be done any time a ship executes a maneuver. You don't have to declare the target and proceed with the attack. Attacking is optional.

That's what I figured, thanks!