Both were extremely drunk at the time, prompting the judge to say he could only hope the "tragic, tragic, tragic" case would draw attention to the fact alcohol and violence do not mix.
He outlined how the two had argued after a prolonged drinking session, tussled and when a cousin intervened Barry jumped on top of him.
Hunt reached for a 2.28kg axe, using it to hit his brother on the side of the head.
"As he was lying unconscious. Your cousin asked you what you'd done, you dropped the axe and burst into tears," Justice Lang told Hunt.
The brothers' older sister, Morrise Hunt, read a heartfelt victim impact statement, also blaming alcohol for the death.
"As whanau, we have asked over and over again how the death could happen when the two were so closely knit.
"It is difficult to describe how our lives have been changed by this, many tears have been shed for both [brothers]," she said.
She told of feeling as if her heart had been ripped out when she saw Barry taken off life support in Whakatane Hospital.
"We struggled to comprehend as we watched the clock ticking as our brother, his daughter's father, was taking his last breath, his last pulse, his last heart beat."
Referring to a visit to "Cam" (Cameron Hunt) in Waikeria, she was adamant there was genuine remorse in his eyes as he said, "I am sorry, sis, I didn't mean to do that to our bro."
Begging for leniency, she said all the whanau wanted was to have their little brother home again.
Hunt's lawyer, Gene Tomlinson, told of the emotion he experienced watching a DVD interview with his client, saying it was 10 minutes before the bombshell was dropped that his brother had died.
"He folded over on his chair, toppled, lay in the foetal position crying not for himself but the loss of his brother."
There could be no greater expression of remorse, he said.
Outside the court, Ms Hunt said she was happy with the sentence.
"We want our little brother back very soon so we can grieve together."
