Then largest of the Armstrong guns only four of these were manufactured the first was of 13.5inch bore.
Subsequent ones were bored to 13inches.
The one shown above was damaged after trials at Shoeburyness. Two more did not survive manufacture.
The only other one that saw experimental service was the one mounted in Southsea Battery.
It was not shown on armament returns as it was not adopted and retained the original shunt rifling.