- Posts: 654
- Joined: 26 Jul 2009 16:14
- Location: Essex, UK
The 15-inch Mk I was modified, starting sometime in the late 1930s, with two significant improvement. One, the maximum elevation of the gun was increased from 20 to 30 degrees, increasing maximum range and two, the projectiles were improved with a more streamlined ballistic cap, giving an improvement of over 5,000 yards.
The battleships and battlecruisers equipped with these guns, were given the upgrades as they underwent overhauls, but none of the R class had received them before WW2 began. Other ships were upgraded as WW2 progressed.
As an alternative improvement, the unmodified ships were given a ‘super charge’ of 490 lbs, the largest propellant charge that the guns and mountings could safely handle. Ships with the 30-degree adjustments didn’t use the ‘super charge’, as it placed additional barrel wear and mounting stress. With the supercharge, maximum ranges range improved by 5,000 yards, 300 yards short of the 30-degree ships.
Now I have some questions
I’m unclear as to whether a ship could simply be issued the 490 lb ‘Super charge’ or required some dockyard modifications to fire using one.
I think the propellants (or charges) were made up from four bags, was the ‘super charge’ simply a fifth charge. If not how easy was it to make these, was it only at the factory, or could dockyard magazines do this work?
Could the HE shell be fired with the super charge, as well as the APC version.
I don’t know of any ‘super charge’ firings, how badly did they wear the barrels and stress the mountings?
I think very limited numbers of HE shells were carried by the ships, I read that the fortress of Singapore, equipped with five of these guns, only had one HE shell. Was there a shortage of HE shells?
I think two (Royal Sovereign and Resolution) R class were enabled to use ‘super charge’ on the class sailing to the Far East in December 1941, is this the case?
These questions are based on my thoughts on the use of the R class for shore bombardment, and how far inland might they reach?