300pd Blackpowder Cannons at Williamstown

by John

The cannon construction techniques which were pioneered by William Armstrong in the 1860’s led to more powerful and more accurate weapons. The 6.3″/160mm bore cannons which were shown in yesterday’s post, (and modelled by me,) were rapidly followed by larger cannons. The larger cannons were required to counter the iron clad steam ships which were replacing wooden warships. The colony of Victoria purchased 9″ muzzle loading black powder cannons for the defence of Melbourne, and yesterday I visited Williamstown to see 4 of them.

The 9″ rifled bore cannons fired projectiles weighing 300lbs! Cannons of this size were described according to the bore diameter, in preference to the weight of the projectile.

A fort was constructed at Williamstown (Fort Gelibrand), and 2 of the cannons are located inside a military establishment, unfortunately not accessible to the public.

As seen from about 20 meters, through the fence. Muzzle loading 9″ monsters. The projectile seen is said to be stuck there.

I was sure that I had seen some photographs of similar guns at Williamstown which were accessible so I asked some locals, and was directed to the foreshore.

That is Melbourne CBD in the background.

These 9″ guns are rifled (6 grooves), made in 1867, and muzzle loading blackpowder. They are very similar to the 10″ guns which were mounted on the monitor HMVS Cerberus, but these are garrison mounts whereas the Cerberus guns were rotating naval mounts.

The 300lb projectiles were loaded using a gantry which was mounted on the end of the barrel. The gantry mounting point can be seen as the small holes in the side of the barrel.
The loading gantry can be seen in this old photograph of one of the 9″ Armstrongs when it was located at Fort Queenscliffe.
A feature of the 9″ cannons was the “Elswick” recoil control mechanism. These substantial strips of iron extended the length of the chassis, and shorter pieces of iron were hung from the carriage to provide friction control of the recoil. The degree of friction was controlled with levers which adjusted the spacing of the strips.

Unfortunately most of the elevation control mechanisms are missing. The small bracket top left was probably to hold the steel rod which was used to perforate the gun powder bag after it and the projectile were positioned.
6 rifling grooves. The projectiles 1867 to 1877 would have had studs to match the rifling. After 1877 the projectiles would have used copper gas checks to engage with the rifling. The inner and outer coil layers of the chase of the barrel can be seen if you look closely.
The 9″ guns were manufactured at the Elswick works, Newcastle, England. and the Royal Gun Factory Woolwich England. The gunmetal trunnion caps are original. If you look closely at the barrel surface you can make out the outlines of the strips of iron which formed the coils.

HMVS Cerberus is a topic for future posts. An excellent source of information is found at http://www.cerberus.com.au