My conversations with shooters in Australia indicate that their massive buyback program was used by many to dump unsellable firearms they no longer wanted.

Government agencies that have formally studied the result found the scheme failed to produce claimed results.

“Although gun buybacks appear to be a logical and sensible policy that helps to placate the public’s fears, the evidence so far suggests that in the Australian context, the high expenditure incurred to fund the 1996 gun buyback has not translated into any tangible reductions in terms of firearms deaths”

https://www.ncjrs.gov/App/publications/Abstract.aspx?id=246605

– National Criminal Justice Reference Service

ABOUT National Criminal Justice Reference Service
Established in 1972, the National Criminal Justice Reference Service (NCJRS) is a federally funded resource offering justice and drug-related information to support research, policy, and program development worldwide.

More:

https://theconversation.com/factcheck-qanda-did-government-gun-buybacks-reduce-the-number-of-gun-deaths-in-australia-85836