On the 26th August 1942 the 103rd Australian Heavy Anti Aircraft Regiment was formed at the Loftus Camp in NSW. Under the Command of Lieutenant Colonel Long, the Regiment consisted of three heavy mobile batteries allotted the numerals 132, 133 and 134.

The personnel from the 33rd Infantry Battalion originating from country NSW and the Sydney based, 45th Infantry Battalion formed a major part of the 133rd Hvy AA Bty.

A number of men from other units that were already skilled in artillery would be attached to the 103 Regiment as well. Units such as the 19th Battery from Sydney, 12th and 26th Battery from South Australia, 33rd Hvy AA Battery from Tasmania and the Victorian based 2/2 AA Regiment. Captain Alan Randle was a member of this particular unit from Victoria that had previously served in the Middle East. Captain Randle would become OC, Officer Commanding of the 133rd Hvy AA Battery and eventually promoted to Major.