In Batemans Bay Local Court on Monday, May 4, Magistrate Doug Dick said the haul included a double barrel shotgun, a Winchester firearm, a pistol, a ball bearing gun, flick knives, tasers, a cross bow, bayonettes, a laser pointer and a butterfly knife.

Appearing via audio-visual link, Jackson Patrick O'Brien pleaded guilty to 15 weapons offences and one drug offence.

He was arrested and refused bail on April 5, 2020.

Defence solicitor Geoff Knox said his client had an unexplained "strange fascination" with weapons, but the firearm's discharge was accidental.

Mr Knox acknowledged "these are serious matters", but said O'Brien had no criminal history, had no intention of using the weapons and "there was no real nefarious thinking".

He had worked for many years as a forensic nurse in Victoria, but personal issues had arisen.

"He felt it best to get out of Victoria," Mr Knox said.

"He now understands his behaviour was destructive and he needs to engage with all support and counselling."

He said O'Brien showed a "willingness to accept his behaviour was strange, to say the least".

Mr Knox drew the court's attention to what appeared to be a black eye his client had suffered in custody.

"It looks as if he has been assaulted in prison," Mr Knox said.

"His time has been tough in there. He could be released today."

Magistrate Dick disagreed.

"Some times people commit offences which warrant jail first up; that is why you have been bail refused," he told O'Brien.

He then warned of the possible maximum sentences: "Firing a double-barrel shotgun carries 10 years; possession of shotgun - 14 years."

One-by-one, Magistrate Dick listed the other weapons which carried heavy jail terms.

"I can accept you had no sinister purpose, but it is a large cache found in a suburban home with limited security," he said.

Some were found in a car and garage.

He noted O'Brien's previous good character, his plea of guilty, his contrition and remorse, but said the situation was dangerous.

"They were loaded, all the ammunition was easily accessible," Magistrate Dick said.

Convicting O'Brien, Magistrate Dick said the court had a responsibility to deter further offending and send general public message of deterrence.

"My purpose is not to crush you, but I have to have regard to all the matters I have mentioned," he told O'Brien.

In imposing one sentence for all matters, he considered "special circumstances", including "because it is your first time and you have no previous history and have learned a valuable lesson in being arrested and confined".

He fined O'Brien $1000 for possessing ammunition and $600 for possessing cannabis.

On all other matters he imposed a six-month non-parole jail sentence and a six month parole sentence, backdated to April 5. O'Brien would be due to release on October 4.

O'Brien's parents were in the court.

"When you are released you should do everything you can to make them proud," Magistrate Dick said.

"I love you mum," O'Brien called.

"We are always here for you," she replied.

"We love you Jack," his father called.

O'Brien shed tears at the exchange.