I gave them a rough estimate of 1 acre which is about 210ft x 210ft or 70 yds by 70 yds. Figured that would give space for firing line, targets, sight-in etc.
I'm actually possibly heading out to meet her today but not sure if it will work out. Thursday is not a normal field day but she's going out there to accept a shipment of some kind. She had the questions you'd imagine - insurance, how far do pellets go, what happens if you overshoot, safety etc.