Roger James Kilby, 40, stole a mobile phone from Andrew John Anthoney's house after a drinking session in the small central western NSW town of Peak Hill on March 2, 2023.
Nine days later, after dancing and drinking at the local RSL, he went back to Mr Anthoney's home to confront the 57-year-old about child abuse material allegedly found on the phone.
Kilby pleaded guilty in February to committing murder after the verbal confrontation escalated into violence.
He was sentenced by the NSW Supreme Court on Monday to a maximum 18 years behind bars.
The concreter left his victim unconscious in his home and was seen by witnesses soon after swearing and screaming in a panic.
"I think I killed this matey down here," he said.
Justice Dina Yehia said Mr Anthoney had been killed by "a sustained and very violent assault involving numerous blows".
While Kilby went to the Peak Hill home over the perceived child abuse material, he had not visited as a vigilante intending to take the law into his own hands, she said.
Instead, the murder was "impulsive and unsophisticated" occurring after the verbal argument worsened.
Kilby had his sentence backdated to his March 2023 arrest when he handed himself in to local police.
He was given a non-parole period of 12 years and six months, meaning he will be eligible for release on September 11, 2035.
The judge found Kilby had shown genuine remorse for his actions and had made positive steps towards rehabilitation while in prison.
This included completing an engineering certificate, being appointed the Aboriginal delegate, leading NAIDOC events within the prison, and having his artwork displayed at an exhibition.
She said his signs of becoming a productive member of society were positive if he could continue getting treatment for his drug and alcohol addiction.
In a letter of apology to the court, the 40-year-old expressed regret and sorrow to his community and said he wanted to become a better man, the judge said.
Kilby sat emotionless wearing prison greens from a room in Bathurst prison during his sentencing.
13YARN 13 92 76
Lifeline 13 11 14
8°C