Just received the 1913 edition of "Halcomb Steel Co. Catalogue and Hints on Steel". After purchase by Crucible in 1911 the company apparently continued to market several tradename steel and steel alloys including ‘Dreadnought High Speed Steel’, ‘Ketos Oil Hardening Steel’, and ‘Halectralloy Brand’ Chrome Vanadium and Chrome Nickel steels.
There is no mention whatsoever of steel for gun barrels nor Royal or London steel.