For about 40 minutes, Gareth Train shot at specialist police as he moved around his remote Queensland property, a coroner has heard.
His brother Nathaniel sat at an outside table and his wife Stacey remained inside their Wieambilla house as Gareth Train fired intermittently in December 2022.
No one from the police Special Emergency Response Team (SERT) returned fire.
"Gareth was more actively standing up, walking around," Detective Senior Sergeant Nathan McCormack told Brisbane Coroners Court on Tuesday.
Gareth Train had even continued to fire at a heavily armoured police BearCat vehicle as it retreated after it had been surprised by a barricade placed on the driveway.
"Gareth was quite open with his movements. He was never barricaded behind anything," Det Sen Sgt McCormack said.
"It appeared to me he was never expecting any return fire."
Gareth Train had also earlier that evening fired at one of the police helicopters circling the property before SERT members arrived following the fatal shooting of three people including two officers.
But at 10.04pm everything changed.
After unsuccessful attempts to negotiate with the Train trio, SERT returned fire.
"That first shot... changed the behaviour of Gareth in particular," Det Sen Sgt McCormack told the inquest into the six Wieambilla shooting deaths.
After the first SERT shot hit a water tank, the Train brothers took positions on the ground with their rifles and began firing at police.
Nathaniel Train bunkered down in an "L-shaped" barricade beside the house that comprised of two hardwood "extremely bullet resistant" logs, the coroner heard.
Stacey Train intermittently emerged from the house, firing a total of three shots.
All three were fatally shot between 10.32pm and 10.39pm.
Forensic coordinator Senior Sergeant Kirsty Gleeson told the inquest 84 police discharged cartridge cases were later found at the scene along with 62 from SERT operatives.
There were 116 discharged cases from non-police firearms but it was unclear whether they were all fired that night.
About six hours earlier, Constables Matthew Arnold and Rachel McCrow had been killed after arriving with two other officers at the property attempting to serve an arrest warrant for Nathaniel Train.
Neighbour Alan Dare was also ambushed by the Trains and shot dead.
SERT members arrived in four vehicles and discovered the Trains had barricaded the Wieambilla home.
Det Sen Sgt McCormack - the lead investigator into the Trains' deaths - said three firing positions had been set up on the property which featured 100 acres of bushland.
Mirrors were placed along the driveway, with SERT members complaining that reflections hampered their vision as they drove toward the home at night.
A log and metal barricade had been placed on the driveway about 100m from the house, stalling the BearCat that then came under fire.
Det Sen Sgt McCormack said satellite imagery of the property showed the barricade and firing locations were already in place in October 2022 - two months before the incident.
Gareth and Stacey Train had bought the property in 2015.
Sen Sgt Gleeson said the Trains' home was set up for "off-grid living".
Cars and a tractor were also strategically parked around the house ahead of the siege.
The property's remote location also created obstacles.
Mobile network problems in the Wieambilla area ensured that police helicopters - SERT's "eyes in the sky" - were unable to stream footage of the shooters.
Instead screenshots of TV monitors were sent via the police computer system to SERT members on the ground to help locate the Trains.
Police communication had also been compromised by the Trains taking the radios of Constables McCrow and Arnold, the inquest heard.
Det Sen Sgt McCormack said negotiators had repeatedly tried to contact the Trains on mobile phones on the night before using the BearCat's loudspeaker.
He said their only communication was a YouTube video posted by Gareth and Stacey Train that night near the house, calling police "devils and demons".
