Background on 18th century British gunfounding – based on mentions in :

Adrian Caruana “The History of English Sea Ordnance” volume 2 (Rotherfield 1997)

Brian Lavery “Carronades and Blomefield guns” in ‘British Naval Armaments’(London 1989)


Up to the early 18th century, most British gun foundries were in the Weald of Kent; in 1717 there were ten gun furnaces operating. These furnaces cast guns from iron ore in loam moulds, set vertically, muzzle upwards, in casting pits.  These were known as ‘Wealden Iron’ or ‘cold-iron’ guns, and had the tendency to be brittle when cold.

During the century there was a move away from gunfounding in Kent to south Wales, northern England and Scotland; northern ironstone was harder than that found in southern England but required higher temperatures for smelting, but this was achieved by use of coke.  This had the benefit of producing iron which was strongest when cold.  Northern gunfounders also started using boring machines – the old Kent process used a cast around a central core, but this was liable to produce distorted guns, the metal shrinking as it cooled. In the 1770s the technique used was to cast a solid, and then bore out the core; this produced a stronger gun with a standard barrel with little or no deviation. 

In 1759 a major move took place with the founding of the Carron Company to set up a new gun foundry in Scotland; by the mid 1760s they had become a major supplier of guns for the Ordnance Board, but they lost their contract in 1773 due to a high failure rate of the guns. This gave the opportunity to others, and new contracts were awarded to John Wilkinson of Bersham, Shropshire, Anthony Bacon of Merthyr, Wales and Walker of Rotherham.

During the 1780s other foundries entered the gunfounding business – Cookson in County Durham, Crawshay in south Wales, Hird Dawson & Hardy at Lowmoor, Yorkshire and Sturgess in Bradford. In addition the Carron company continued in business as did Walker.

Walker seems to have emerged as the prime contractor for the Ordnance Board – he was chosen in 1787 to work with the new head of the Ordnance Board, Captain Thomas Blomefield, to produce a new pattern of gun and by the 1790s was regarded as the premier gunfounder.

Caruana states that Walker melted down old ‘Wealden’ guns to recover the iron. This was a technique developed by Walker; mixing old charcoal smelted iron with the local iron ore gave the mix greater viscosity – when molten the local ore ‘poured like treacle’, but when mixed with Wealden iron it ran like water.  This also had the effect of considerably reducing the sulphur content and gave the guns a mottled appearance, sometimes referred to as ‘grey iron’

The design of the guns was the responsibility of the Ordnance Board and in 1780 Captain Blomefield became Inspector of Artillery for the board. From 1786 he undertook a redesign programme for British naval artillery, and he worked in conjunction with Samuel Walker.

During 1786 and 1787 a series of trial pieces were produced by Walker, with varying degrees of success, the design being modified in light of their experience. One major breakthrough came when Walker successfully managed to incorporate a loop, not previously possible on an iron gun - “We have hit upon a mode of casting and boring guns with loops on the cascables....” 

From 1794 all new guns cast (with a few exceptions) were to the Blomefield design and they rapidly replaced the old models – by 1808 few old pattern guns were left.