When Tasmanian firearms dealer Peter Thurley passed away in 2014, buried among the possessions he left for his family was an old, battered gun with a hollow handle and a mystery.

"We got one each, the three brothers," Peter's son Dean Thurley said.

"I got this one."

Mr Thurley said the gun had been given to his father in the 1980s by a North-West family.

"There was a note in the barrel that said it was from the Mason family on the North-West Coast," he said.

"I think my dad wrote it, but that's as far as he got, he didn't have the time to chase it up."

Mr Thurley, of St Leonards, said the gun's story immediately captured him, and he contacted the manufacturer as a first port-of-call.

"I've written to Colt, who manufactured the gun in 1881," he said.

"They said it had been sent to their retailer in London. It would have been purchased there, and they would have had records, but they were lost during the second world war."

Not in the least bit turned off, Mr Thurley also contacted the Australian Antarctic Division.

"I grew up around guns," he said.

"I could see the gun had been lightened by one or two pounds.

"Any of the metal that was on it for mainly decorative purposes has been removed. The stock itself - which is the wooden part - the inside has been hollowed out so you can see through it.

"There's no reason to cut a shotgun down and lighten it unless you're going on some sort of expedition."

"I'm just trying to get another piece of the puzzle," he said.

"If it can be linked to Antarctica, it probably needs to go to a museum.

"I'm not so much worried about what it's worth, I am more interested in what it has seen, the places it's gone.

"I know firearms aren't everyone's cup of tea. But it's not a machine gun or anything silly like that, it's an old gun with a story."