The 15-inch Guns of HMS Vanguard, Courageous and Glorious and other battleships.
The general belief is that HMS Vanguard's 8 main guns, their mounts and turrets came from HMS
COURAGEOUS and HMS GLORIOUS, when these were converted to aircraft carriers.
Records, formerly kept at Priddy's Hard (Naval Armaments Depot, Gosport) included the 15 inch gun registers. These were essentially logs, with one page for each gun, giving details of allocations, rounds fired etc. It was clear from this log that although Vanguard's main turrets and mounts came from Courageous and Glorious, only one of the big guns came from one of them - and that was indirectly, as it had been in HMS WARSPITE in the intervening period.
It seems that Vanguard's 15 inch guns came from :-
HMS QUEEN ELIZABETH (2)
HMS RAMILLIES (2)
HMS ROYAL SOVEREIGN (1)
HMS RESOLUTION (1)
HMS EREBUS (1) (monitor)
HMS WARSPITE.(1)
The life of the liners was between two and three loadouts (ie. around 200 shots) for each ship. The Royal Navy held a pool of heavy guns - about 170 15 inch guns These were rotated among several ships and refurbished during their intervals ashore. The 8 guns removed from Courageous and Glorious went to Malaya, Renown and the monitor Roberts as well as Warspite.
There were 184 15 inch guns manufactured by six different works:-
Armstrong Whitworth completed 34 at their Elswick Works (Newcastle)
and 12 at their Openshaw Works (former Whitworth factory in Manchester).
Beardmnore completed 37 at Parkhead. Glasgow,
Vickers 49 at their Sheffield works.
Royal Gun Factory 33 at Woolwich.
Coventry Ordnance Works 19.
Coventry Ordnance Works was an interesting company. Potential builders of export battleships like John Brown, Cammell Laird and Fairfield were held to ransom in quotes for big guns from Armstrong and Vickers, who had a virtual mon/duopoly in the UK. So they set up Coventry Ordnance Works in 1905 to provide themselves with a capability to manufacture guns and mountings. The heavy mounts were manufactured at Scotstoun, Glasgow.
The history of 15-inch mounts is even more interesting than the guns. The two 'surplus' twin turrets from RENOWN and REPULSE evolved after they became 6-gun battlecruisers instead of 8-gun battleships. The net effect was that there were four 'spare' turrets which were allocated to COURAGEOUS and GLORIOUS. Glorious's two came from Vickers Barrow works while Elswick did Courageous's A turret and Coventry Ordnance Works her Y turret.
These four turrets were removed during their carrier conversions in the late 1920s and kept in store. As it would take too long and too many resources to build the twelve triple 16-inch turrets for the four LION class battleships in 1940, it was proposed to use instead the four spare 15-inch turrets to arm one new battleship, namely VANGUARD.
The four turrets were shipped to Scotstoun for refurbishment at the former Coventry Ordnance Works , now operated by Harland & Wolff . They were then shipped in VANGUARD only a few miles down the Clyde in 1944.
All guns and turrets were scrapped with the ship at Faslane 1960-61.