Police are treating the incident as a deliberate attack but say they have no evidence why the couple would have been targeted.
Police are searching for the vehicle, which fled the scene.
"It's obviously very, very concerning - the fact that two people were sleeping in this when a firearm was discharged," Peachey said.
"We've very lucky it's not more serious."
It's believed the shots were fired some distance away from where the man, 65, and woman, 56, were camping in an area not easily visible from a nearby road.
"There's a little bit of distance, which indicates it could possibly be a rifle."
Police confirmed it was a gun attack.
"We do believe we'll be able to recover at least one of the rounds."