Police prosecutor Andy Horne told the court McCurrach had stopped and unpacked camping equipment to boil some water to make tea when he noticed movement.
Thinking it was a deer, he looked through his scope to identify what he was looking at.
Unable to identify what the movement was, he lowered his newly purchased .308 calibre rifle and used his home-made roaring horn to imitate a stag's roar, hoping what he believed was an animal would show itself.
After increasing magnification of the scope to help identify the target, he saw more movement to the left of where he thought the deer originally were.
After arriving the previous day and noticing several people in the area, making him feel uneasy, McCurrach had decided to go home.
He had climbed up the Sparrowhawk Bivvy Track about 8.30am on March 31 to find cellphone coverage to phone his wife and tell her about his departure.
While walking up the track, two deer ran in front of him and he soon sidled off in the same direction as them.
He could hear several stags roaring in the area and roared back at them with the horn.
The defendant continued hunting through the tight bush area and sidled back around and up toward the ridge to where the track was.
Meanwhile, Mr Jordan's hunting party, who had planned to travel up the track and hunt around the sub-alpine area, stopped to rest.
Mr Jordan sat on the edge of the track, Mr Clark to the side of him and their companion opposite.
Positioned above the other hunting party, McCurrach, believing he was looking at the shoulder of a deer, closed the bolt of his rifle and fired a single shot.
Mr Jordan was shot in the upper neck area from a distance of 42m, killing him instantly.
Mr Clark and their friend's hunting dog were hit by bullet fragments which disintegrated from the impact with Mr Jordan.
Initially unaware their friend had been killed, the others sought cover and yelled at McCurrach.
The defendant walked out from the position he had fired from and immediately realised he was within two to three metres of the track that he had been walking up earlier. He was initially confused about what had happened, a personal locator beacon was activated and emergency services arrived.
Bullet fragments remain in Mr Clark's leg. A doctor said it would likely cause damage to try to remove them.
While entering the Ruahine Range is unrestricted, the Department of Conservation requires those wishing to hunt to hold a valid hunting permit, which McCurrach did not have.
The summary states: "It is a relatively simple and straightforward task to obtain a hunting permit for an area". It is obtained electronically through a website and covers specific areas and time-frames.
Mr Horne told the court McCurrach had been fully co-operative with police.
The maximum penalty for carelessly using a firearm and causing death is three years' imprisonment or a $4000 fine.
Judge Rea ordered a probation report and remanded McCurrach on bail to return to court for sentencing in September.
