English cast-iron cannon had become practical by 1543. Bronze pieces were lighter for the same shot weight and tended to crack when they failed, while bulkier iron guns could burst. An individual iron gun cost about a third as much, and the advantage grew when equipping a fleet because iron was easier to obtain in the necessary quantities and quality. The estimated total cost could fall to 15-20 percent of an equivalent bronze program once material sourcing and production time were included. The two successive ships named Victory illustrate that timing difference: collecting and casting the bronze battery for the earlier ship took years, while the later iron battery took months. By 1794, rated ships of the fifth rate and above required roughly 12,000 guns in commission, while ships in ordinary, guardships, fortifications, and stores pushed the inventory estimate toward 20,000. Iron made that scale of armament affordable despite the disadvantages of the individual weapon.
Chapter · 49:01-57:36
Cast-iron cannon made fleet-scale armament affordable
Iron guns were heavier and less safe than bronze pieces, but lower costs and scalable materials made thousands of fleet weapons practical.