From Smallest Minority comes a link to the end result of registration, this case from New South Wales in Australia.
Money quote: "Mr Moroney said that, as part of the blitz, thousands of weapons were destroyed because police were not satisfied that the firearms were being kept securely, or that "possession of that firearm was necessarily further warranted"." Please note, they minions of the state decided either they didn't like the way the owners stored them, or decided the peasants didn't 'need them anymore'; so they stole private property to be destroyed.
Also note, the registration system there means that the cops can show up at your home any time they like to 'inspect' your storage and decide if they think you should be allowed to keep your property.
This is directly related to a bill some jackass tried to pass here a few years ago stating that if you owned more than a certain amount of ammo/I think it was 1000 rounds/ you would have to have an 'arsenel' license from the feds, which would entitle them to inspect your home and 'storage' any time, day or night, with the usual threat of arrest & confiscation if they didn't think you were within their specs.
Never, NEVER register your arms with some government flunky; they and the nannies will screw you with it.