What are the laws in Australia for purchasing and obtaining a firearm?

Step one: Obtaining a gun licence
 
  • must be over the age of 18 for a firearm licence. But can apply for firearm minor permit if under 18 years. 
(1) identify your 'genuine reason' for wanting a gun licence: sport/target shooting,  recreational hunting, primary production, pest control, business or employment, rural occupation, animal welfare, firearm collector.
(2) Depending on your genuine reason/s you will need to provide the required proof for that genuine reasons i.e.: proof of club membership, proof of employment, proof below to collector society, proof from accountant or solicitor that you are primary producer or employer that you are a security guard etc.
(3) obtain an application form for a  firearm licence
(4) Complete a multi-day firearm safety course. Pass a written test and practical assessment which will provide certificate that you have passed and completed course.
(5) Compile your firearm application form:
  • Identify your genuine reasons for a firearm
  • Identify Category of firearm you require: A, B, C, D and/or H. For  D (most lethal firearms. For category D (Self-loading rifles and shotguns), applicant must show "special reason" as to why the applicant needs such a firearm and why a less lethal firearm would not fit the purpose.
  • attach safety training completion certificate
  • declaration that you meet safe storage requirements for the firearm category you are seeking. Firearm storage is generally not inspected but random checks are allowed.
4) Firearms Registry processes your application and conduct background checks: includes - criminal record and any court ordered mental health orders and intelligence checks.
 
If you have a record for a 'prescribed offence' then you cannot obtain a gun licence including:
  • sexual offences
  • Violent offences
  • Offences related to prohibited drugs
  • Robbery
  • Terrorism-related offences
  • Offences relating to organised crime and criminal groups
  • Firearms or weapons offences
  • Fraud, dishonesty and stealing offences5) Wait at least 28 days for checks to be conducted and application processed.
6) If your application is approved you will be sent a letter. You then go to what is known as the Road Traffic Authority wit the letter and your proof of ID. RTA will take your photo, you pay a fee and RTA will issue and firearm licence.
 
Note: for a first time applicant foe a handgun licence the applicant may only apply for what is known as a probationary pistol licence. a PPL is issued for six months and the licence holder may only use the handgun at a gun club or under supervision by a person who has a full handgun licence.
 
Step two: To obtain a gun
 
  1. Lodge a permit to acquire (PTA) application. A PTA must be lodged for each firearm
  2. The firearm type must correspond with the firearm licence category you have
  3. On the PTA form the applicant must:
 to identify address where firearms will be stored.
Type of firearm category they are seeking
declare can comply with safekeeping requirements and have a good reason for acquiring the firearm. The good reason must relate to the 'genuine reason'.
  1. For permit to acquire a handgun (include semi-automatic) official from pistol club must complete part of the form
  2. attached the fee required
  3. send PTA application to Firearm Registry
  4. There is a mandatory  28 day waiting period to complete further background checks. If your PTA is for a second or subsequent hunting rifle then background checks are not conducted.
  5. Once you have the PTA you take it and firearm licence  to Licensed Firearms Dealer
  6. You can purchase a firearm/s
  7. Firearm dealer will notify Firearms Registry of the purchase.
  8. The firearm will be recorded on the Firearms Registry database system
Facts Sheets
(The fact sheets are from the state of New South Wales. Although the laws are similar in the other states and territories they do vary.)
Firearm categories

https://www.police.nsw.gov.au/__data/assets/pdf_file/0007/133198/FACT_SHEET_Firearm_Types_V1.4_Nov2017.pdf

Steps for obtaining a licence
Category D H (handguns)- High powered firearms
Depending on your genuine reason you may require an authorised letter or signature on your form from their Accountant, Solicitor or Tax Agent or intention of employment letter.
List of genuine reasons for obtaining a firearms and type:
Obtaining a semi-automatic handgun licence:
Permit to Acquire:
Safe storage requirements:
Fingerprinting and State of  Victoria