Under the scheme, launched today, owners of unregistered, illegal or unwanted firearms can hand them in at any police station until 31 October without penalty.

Police received 1700 guns and accessories - including silencers - during the last amnesty in 2009, according to Police Commissioner Gary Burns.

"Two hundred firearms are stolen each year," he said.

Attorney-General John Rau said the recent increase in penalty for people caught with unregistered guns or without a licence had spurred the amnesty.

"It was considered by the government that it was only fair that in the context of that dramatic ramping up of penalties for firearms that we co-ordinate it with an amnesty," he told reporters in Adelaide.

The penalty for possessing an unregistered or illegal firearm is up to $50,000 or up to 10 years jail.

A similar amnesty in 2008 netted 1100 firearms.