In what was described as a ''sad chapter in Navy's history'', the Department of Defence said it acknowledged the lack of support the Carriage family received after youngest member Max Carriage was killed by ordnance he found at the Beecroft shelling range in 1957.

''In a mediation process conducted in late 2008, Navy formally apologised to Mr [Allan] Carriage over Navy's treatment of his family after the incident,'' Defence said in a statement.

Mr Carriage said this week the news had lifted a great weight from him.

''When they approached me I didn't believe it at the time. I felt quite relieved when they offered us the mediation. I was still hurting about the whole situation because it shouldn't have happened in the first place, you know,'' he said.

''They've done the right thing by us by just recognising what they did.''

Max Carriage, 10, was walking through the naval bombing range with his family on September 6, 1957. He picked up a large bullet and upon return to his Aboriginal fishing camp at Hammerhead Beach, started tapping it.

The shell exploded, killing him instantly. It also blew off his father's hand and badly burned another brother, Peter.

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