(YahooNews) - A man with links to the Mongols bikie gang has pleaded guilty to more than three dozen charges relating to the discovery of an extraordinary cache of guns, drugs and cash found in a suburban Belmont house.

Justin Rinaldi, 38, had been due to go on trial at Perth's District Court today, following the discovery of kilograms of meth, MDMA and cocaine along with 14 high-powered firearms and more than $300,000 in cash.

But instead, he pleaded guilty to all 39 charges, which also included the possession of a jamming device, which could have been used to prevent police communicating with each other during an operation.

The police search at the home in Williamson Street in February 2014 found the guns, drugs and money in a wine cellar in the home, which also had a fortified front door.

The weapons included automatic pistols, including one with a silencer, seven rifles and thousands of rounds of ammunition. A .357 Magnum was found in Rinaldi's unlocked car.

At the time of Rinaldi's arrest, police said the man had links to the Mongols outlaw motorcycle gang, with prosecutors today saying their belief was that he was selling the drugs and the guns.