Gadget and the backroom boys: Domenic Perre’s NCA bombing trial hears details of his business dealings with gunsmith Allan Chamberlain

NCA bombing suspect Domenic Perre wanted to go into business with a “gadget” expert who “magically” made guns more lethal, a court has heard.

Allan “Gadget” Chamberlain outside the Supreme Court. Picture: NCA NewsWire / Morgan Sette.

The key witness in the NCA bombing trial was nicknamed “Gadget” because he could “magically” make guns more lethal – and Domenic Perre wanted to go into business with him, a court has heard.

Allan Chamberlain has also told the Supreme Court he agreed to held hide Perre’s extensive gun collection from police in the wake of a drug bust as a favour, because it would “be financially beneficial to me”.

On Thursday, he said he first came to know Perre in 1993, the year before the bombing, through a shop called Central Firearms.

Mr Chamberlain said he had worked as the shop’s unofficial gunsmith while Perre was one of its regular customers, earning him special rights in the store.

“I called them ‘the backroom boys’ (because) rather than coming in through the front of the shop, they entered through the back door,” he said.

“It was a cheerful, outgoing place … I enjoyed the company of people who had like interests, the camaraderie of it … they gave me the nickname ‘Gadget’ because I was always tinkering with something.”

Perre, he said, had first approached him about purchasing body armour – and later about counterfeit police badges – before suggesting a business arrangement.

“I had not only the skills but the knowledge to convert semiautomatic weapons into fully automatic weapons … (the owner) would hand me a gun and say ‘do your magic on this’,” he said.

He said Perre provided the machined metal pieces needed for the conversion, he performed the work, and they split the resultant profits 50-50.

“There was nothing in the shop I tried to hide … the conversions were done on a trust basis,” he said.

Domenic Perre being led into court following his arrest. Picture: NINE NEWS.

Perre, 63, has pleaded not guilty to murdering Detective Sergeant Geoffrey Bowen and attempting to murder lawyer Peter Wallis with a parcel bomb in March 1994.

Prosecutors allege that, in 1993, Perre asked Mr Chamberlain – who once shot himself in the chest to demonstrate a bulletproof vest – to hide his gun collection from police.

Weapons seized, by SA Police, from Mr Chamberlain’s home, in the days following the NCA bombing.

Prosecutors allege the weapons belong to Perre, while defence counsel claim they belong to Mr Chamberlain.

They further allege that, the day before the bombing, Perre also gave Mr Chamberlain books, three lengths of detonation cord, 11 detonators and a telephone debugging device to store.

Perre’s counsel, however, say the “Pandora’s box” of weapons belonged to Mr Chamberlain, who had warned a neighbour he could “blow you away” without “being anywhere in sight”.

SA Police evidence photos of items found at Mr Chamberlain’s home during a search after the bombing.

A length of cord recovered, by police, from Mr Chamberlain’s home in a search conducted after the bombing.

Continuing his evidence on Thursday, Mr Chamberlain said he had rarely socialised with Perre, who had been “adamant” that he did not drink.

“It would appear we spoke on the same level of interests – firearms, vehicles, badges, things such as that,” he said.

“On one occasion in 1993, I went to his house to look at some badges he said he had … whilst not necessarily legal, they were interesting,” he said.

“In my opinion they were poor quality renditions … one was a star badge, like an old-time sheriff, the other was a shield badge like the police would have.”

He said Perre was “not angry, but antagonistic” about the demise of a lucrative NT drug crop which, prosecutors allege, formed part of his motivation for the bombing.

“He brought the subject up, essentially telling me he was under a lot of, I believe, financial and mental stress,” he said.

“He was fidgety, for want of a better word.”

He said that, in the latter part of 1993, he agreed to store firearms for Perre, who was “fearful” police would raid his home.

“I was of the opinion that if I did this favour for Mr Perre, in the future it would be financially beneficial to me,” he said.

The trial, before Justice Kevin Nicholson, continues.