The EOC 8 inch 40 caliber were a family of related 8 in (200 mm) 40 caliber naval guns designed by the Elswick Ordnance Company and manufactured by Armstrong Whitworth for export customers before World War I.
Users of this family of gun included the navies of Chile and Portugal.
[1] The EOC 8 inch 40 caliber family of guns originated in 1893 from the Elswick Ordnance Company Pattern P gun which was first produced for export in 1893 and did not serve on board ships of the British Royal Navy.
It was felt that the 7.5 inch guns 200 lb (91 kg) projectile was the limit of what a two-man crew could manage.
It wasn't until 1923 after the Washington Naval Treaty that 8 inch guns began to reappear on British cruisers.