Peter
Firearms in Australiaare controlled under State legislation. The Federal Howard Goverment buyback saw a national tightening of firearms control but there still are differences in legislation and regulations between the 7 States and 2 Territories. The handling of de-acts does vary state to state.
In WA is is very difficult to hold a Licence for any modern semi auto rifle, especially if it is of military origin. Being a de-act does not change this.
Paul