The 6-inch gun emplacements

Construction of the two 6-inch gun emplacements at Bickley Battery formed part of the £8,471 contract awarded to Todd Brothers Builders, a Leederville and West Perth–based firm. Work on the emplacements commenced in September 1937, marking one of the final major stages in establishing the battery’s operational capability.

 

The battery was equipped with two 6-inch BL Wire Mark XI naval guns. These guns were primarily intended for close defence, with an effective range of approximately 16 kilometres. From Bickley Point, they were positioned to protect the South Passage shipping channel between Rottnest Island and Carnac Island, as well as waters within the operational boundary of Fremantle Port.

 

Originally manufactured in 1904, both guns were repurposed naval weapons sourced from WWI-era Australian warships, HMAS Melbourne and HMAS Brisbane. Each gun fired armour-piercing projectiles weighing approximately 45 kilograms, designed to damage or disable enemy vessels attempting to approach the harbour.

 

Changes to the original plan

Early planning for Bickley Battery had allowed for three 6-inch guns, with the third intended as a reserve. This approach was consistent with coastal defence practice at the time, providing redundancy in the event of damage or prolonged engagement. However, due to several factors, including shortages in the availability of suitable 6-inch guns, only two were ultimately installed (The Coast Defences of Western Australia).

 

While the gun emplacements were still under construction at Bickley, both 6-inch Mark XI guns were temporarily mounted on semi-portable platforms at Swanbourne. This interim measure reflected growing political and military concerns in Europe during the late 1930s and allowed the guns to be brought into service quickly if required (The Coast Defences of Western Australia).

 

Installation and commissioning

Construction of the Bickley Battery was completed in April 1938. In September of that year, both guns, numbered 2286 and 2290, were transported to Rottnest Island for permanent installation on Pedestal Mark VI (PV6) mountings. These mountings provided a stable, fixed base suitable for sustained coastal defence operations.

 

Although installed in 1938, the guns were not immediately operational. They underwent a process known as proofing, in which test firings were conducted to confirm the integrity, accuracy and safety of both the guns and their mountings. This process was completed on 25 July 1939, at which point the battery became fully operational (Oliver Hill Battery Conservation Assessment). Bickley Battery was officially recorded as complete in December 1939.

 

Post-war decline and removal

Following the end of the war, Bickley Battery was placed into long-term storage in 1946. As coastal artillery became increasingly obsolete in the post-war period, the battery’s role diminished. In 1963, both 6-inch guns were removed from their mountings. One was sold for scrap and most of the underground equipment was also removed at the same time.

 

 

References

Oliver Hill Battery Rottnest Island: Conservation Management Plan. Completed on behalf of the Rottnest Island Authority by Palassis Architects (December 2005).

 

Oliver Hill Battery Conservation Assessment for Rottnest Island Authority. GB Hill & Partners Pty Ltd (November 2005).

 

The Coast Defences of Western Australia 1826–1963: A Study. R. K. Glyde (printed 1991).