A masked gunman who shot two women during a horrific home invasion and robbed six Canterbury pubs and bars at gunpoint, making off with $115,000 during a five-week reign of terror, has today been jailed for 13 years, eight months with a minimum non-parole period of six-and-a-half years.

Douglas Anderson Roake, a 23-year-old who worked as a security guard at All Blacks legend Richie McCaw's wedding, was "operating in a violent fantasy world" during his violent outburst that has his family mortified, and wondering just what was behind it.

"Seemingly this offending has come out of nowhere," Crown prosecutor Barnaby Hawes told Christchurch District Court today.

The court heard how Roake - who has no criminal history - used high-powered firearms to target licensed premises and demand cash from the tills, safes and gambling machines.

Traumatised victims gave harrowing accounts of his brazen and terrifying crime spree today.

It began on March 10 this year, when he entered Christchurch's Tavern Harewood wearing a black balaclava and wielding a pump-action shotgun at about 10.40pm.

Roake pump-actioned the shotgun twice before telling the duty manager to put the cash from the safe and gambling machines into the bag.

"Stay still and I won't hurt anybody," Roake said.

The duty manager put $18,982 into the bag.

Four days later, he went to The Brickworks Bar, again with a long-barrelled pump action shotgun and demanded cash. He got away with $43,000.

On March 24 shortly before midnight, he hit Trevino's Restaurant and Bar in Riccarton, stealing $29,708.

Five days later he returned to The Brickworks Bar, blasting his way in through a locked front door, getting $12,000.

Carrying a long-barrelled SKS rifle, with its wooden stock cut off, he entered the Springston Hotel on April 6 at 10.30pm.

During the robbery, he threatened several patrons that he would "blow their heads off". He twice fired shots into the roof.

As he fled with $10,000, he told patrons not to follow or he would murder them.

It all came to a terror-stricken crescendo on April 19.

At about 10pm, he went to a farm at Newtons Rd, Rolleston where Nicola Dawson and her daughter Michaela, with her four-month-old son, lived in the main house.

Michaela, 27, had previously met Roake through her ex-partner.

Her aunty Deidre Dawson lived in a barn at the property.

Heavily-disguised, with a black woollen hat with the eyes cut out, Roake entered the farm carrying a long-barrelled pump action shotgun and black sports bag containing a mallet.

As Deidre was putting items in her car parked outside, Roake appeared, pointing the gun at her.

He ordered her into the house.

While Roake was distracted, she managed to flee and phone police.

Roake blasted two shots into the locked front door of the main house, where the mother and daughter had been watching TV.

He told them to get on the floor and demanded money and keys to a car.

Michaela, believing she was going to be killed, refused to lie down, and tried to grab the gun.

During the struggle, his balaclava came off and she recognised Roake straight away.

Meanwhile 53-year-old Nicola ran from the room and phoned police, as well as her son who lived nearby.

Roake hit Michaela with the mallet, aiming at her head, before shooting her in the leg.

She tried to run away, and Roake was bashing her again with the mallet, when Nicola came back into the room and tried to strike him with a vase.

He swung the firearm to Nicola and he told her: "I'm going to shoot you".

He shot her in the stomach, causing her to fall to the floor.

Her son Creighton had then showed up. Roake aimed at his head, but was out of ammunition.

In an emotional victim impact statement today, a haunted Michaela said it "terrifies me every day that he came to kill me".

"Having a gun held to your head is one of the scariest things in the world," she said.

Nicola, whose husband died two years ago, said if she hadn't tripped when Roake had shot her, her severe injuries could have been fatal.

The "abhorrent, deliberate home invasion" haunts her also, and she no longer feels safe in her own home.

"Our lives will never ever be the same," she said.

Both women spent 12 days in hospital, undergoing surgery, and say they'll be affected by their injuries for the rest of their lives.

Creighton Dawson said that hearing her sister yell, "Mum's been shot", will forever send chills down his spine.

After the home invasion, Roake fled to Ashburton where he held up the Turf Bar at Ashburton Hotel.

"This is a robbery, get inside, and lie on the ground," he said.

He fired a shot into a wall and then two more into the cash till as he tried to open it.

He took $1645 in cash from the safe before fleeing to an address at Rakaia Huts.

Police found him the following morning where he admitted the Ashburton robbery.

He earlier pleaded guilty to six charges of aggravated robbery, two charges of wounding with intent to cause grievous bodily harm, and two charges of presenting a firearm.

None of the cash has been recovered.

Today, an 18-year-old waiter at Trevino's has been diagnosed with post-traumatic stress disorder (PTSD) and experiences daily flashbacks.

Springston Hotel bar worker Karen Gardener felt it wasn't about the money for Roake, but the thought of having power of his victims.

He held them at gunpoint for 17 minutes, pointing it directly at their heads and bodies.

"Our earthquakes lasted approximately one minute - imagine if one of them had lasted 17 minutes ... now you can appreciate how 17 minutes could feel like a lifetime," she said.

Roake's family, along with police, had "searched exhaustively" to try and establish exactly what caused the violent, extreme crime spree, defence counsel Jonathan Eaton QC said.

The usual explanations of drug addiction, connections to criminal underworld, desperation, or gambling, aren't present in Roake.

Roake has been diagnosed with autism spectrum disorder, formerly known as Asperger's, and in the months leading up to the events, had been "completely obsessed" with competition bodybuilding and strongman events, Eaton said.

He was abusing testosterone supplements, which Eaton said can cause anxiety and aggression, and had been existing on energy drinks.

"When we look back at it, Douglas Roake was operating in a violent fantasy world," Eaton said.

Judge Jane Farish said police, lawyers, family, and victims were "baffled" by his out-of-character actions.

Roake had said he wanted money to buy anabolic steroids which would give him an advantage in strongman competitions - an explanation that Judge Farish found to be bizarre.

She found that Roake had been affected by the adrenalin on, and discharging the firearm spurred his offending on.

Judge Farish granted him discounts from his sentence for being of previous good character, his relative youth, remorse, mental health or capacity, and entering an early plea of guilty.

She jailed him for 13 years, eight months with a minimum non-parole period of six-and-a-half years.

Some members of the public gallery, including victims, were clearly upset by the period of imprisonment.