A JEWELLERY maker produced sub-machine guns in his suburban home, selling them through an organised crime syndicate for $15,000 each.

JAILED GANG FOUNDER'S LINK TO OUTSIDE WORLD

Backyard arms trader Angelos Koots admitted making up to 100 of the perfectly constructed MAC 10 machine guns - more commonly seen in war zones and believed to have been used in Sydney gang shootings - at his Seven Hills house.

The guns, sold with two magazines and a silencer, were of such quality that during "Mythbuster" style tests alongside a genuine MAC 10 they fired 600 rounds a minute.

Sydney District Court heard that Koots made the guns for an associate who had links to outlaw motorcycle gangs.

The high-powered made-to-order weapons were then sold at meetings organised by a Penrith gym owner and another syndicate member, with the transaction taking place opposite a McDonalds in Glenmore Park.

When police raided Koots' house, police found diagrams, blocks of aluminium and steel, steel offcuts and moulds matching the MAC 10 machineguns.

Koots was convicted in relation to four guns after getting an immunity provision for giving evidence against other syndicate members. But under cross-examination by crown prosecutor Gary Corr at a hearing in Penrith District Court, Koots admitted he'd manufactured up to 100 of the guns.

Prosecutors believe at least one of the guns may have been used in a high-profile assassination attempt of an OMCG member, but this never made it into evidence.

Judge Jennifer English noted the operation was "highly organised criminal activity" involving "an ultimate purchaser, a manufacturer and a mastermind".

Joe Tomei, 46, of Bossley Park, who police said had OMCG links, was the mastermind. However, the purchaser was an "undercover operative" known only as John, working for the police.

Police set up Strike Force Silverwood to target Koots, Tomei and another syndicate member, Daniel Parkes.

On August 12, 2010, Parkes gave John one of the weapons, a silencer and two magazines in a shopping bag in exchange for $15,000 in a brown McDonalds takeaway bag, court documents said.

On September 2, they met again and John bought another machine gun, silencer and two magazines in a pink shopping bag for $15,000.

After each sale the money was taken to Pure Fitness, Penrith, where it was held by gym owner Ryan Tierney before being passed to Tomei, the court heard.

On September 8 Tomei went to Koots' house on Margaret St, Seven Hills, where he asked him to make two more guns which were to be sold to John.

In October, Koots delivered the guns, two silencers and four magazines to Tomei's house in a box.

Police conducted raids the same day on several premises and seized the weapons.

They also found other firearms not manufactured by Koots, who also worked as a jewellery maker.

Koots told officers he was making the guns on the order of Tomei who was a friend of his father and used to be the "local barber".

Koots was warned "not to talk" when he entered custody, the court heard.

Judge English told the court Koots's claim that he was not paid and only given a tumble dryer for making the guns was "almost inconceivable".

Parkes, who was also facing other charges, pleaded guilty and was sentenced to nine years jail with a nonparole period of six years and six months.

Koots pleaded guilty and was sentenced to a nonparole jail term of four years with a maximum term of six years.

Tomei has pleaded guilty to knowingly selling a firearm on three occasions. His sentencing will continue on November 22.