115 mm Cartridge from 4.5 inch mk 6 gun

[Tony Williams]

Yesterday I was at Shrivenham wandering around their weapons hall (as one does) and noticed a complete round of 4.5 inch Mk 8 naval ammo. Fixed ammo, but with the deep annular grooves around the neck...so I'm thinking that my case originally had such grooves but they were flattened out by chamber pressure on firing.

I'm returning next week with a camera and a tape measure....

 

[charley777]

Yes, i think the grooves on the Mk8 are parallel, whereas they are in a spiral (like a giant thread) on the shorter, seperately-loaded cases.
And, as mentioned above, the closure lid screws into that. However, i have seen a reference to the short-necked cases also being used as fixed ammo.
Is this possible? I don't know....but i display my 113x640R case with a projectile inserted, just because it looks good (to me anyway, LOL)

 

[Tony Williams]

The Shrivenham round (actually, they have a couple...) has the shell attached and the case measures 700mm. It has the usual annular grooves around the neck. The shell is almost as big as the case: the total length is 1240mm.

 

[2pounder]

Tony if you want more confusion on these The Rotunda had a selection of 4.5 rounds with various closures and necks, not sure if they went to Fire Power exhibition or may be in storage, My photo is pre digital.

 

[Tony Williams]

Here's one of the Shrivenham rounds.

 

[2pounder]

picture of various 4.5 at the rotunda

 

[Tony Williams]

Interesting - there's quite a variation in case size there, with the first complete round on the left having a much slimmer case. I'd like to know the development history...

 

[charley777]

Yes, and the second from left looks quite broad................development history would be very interesting to know....