G'Day Fella's,

Viking338, up until a few years ago, it was still completely legal to own a firearm sound suppressor/silencer/moderator/Can, here in the ACT but when that law changed it was uniformly illegal to possess the now "Prohibited Articles" without a "Police Commissioners Permit" (from the state you reside in)!
When the law changed down here, I made inquiries about what justified a Suppressor/Can?
IIRC, both my own solicitor and the AFP F/arms Rego down here confirmed that it was; "The Threaded Portion or Bayonet Mount That Attaches To the Firearm" was the key part!

Hope that helps

Doh!
Homer