QF 18Pr Mark 1 shells

[Alan1]

Here is a pic of three 18Pr Mark 1 shrapnel shells, fired, retrieved and silver plated. Presumably they were the first fired by a unit after issue of the new equipments in June 1904, or some time shortly thereafter. And, also presumably, they were used as ornaments in a Mess or possibly presented to, eg, the Commanding Officer. They illustrate the variety of ammunition available at the time. Left to right, manufactured by EOC, and heavily stamped as is often the case for this maker, and dated 20.7.05, P Co - the first letter(s) indecipherable, dated 5/1905, the third also by P Co and dated 11/1905. The fuzes are 80 mark 2 by Vickers, Sons and Maxim dated 4/07 and Royal Laboratory, 80 mark 2, dated 3/07. Shame the EOC shell is missing its top ring and fuze, and later corrosion indicates relegation to shed or garage for some many years before I had opportunity to rescue them.
Alan1.

 

[Darkman]

Maker P.Co is Projectile Co. Battersea, London.

They have been nickel plated (the chromium plate top coat not coming into use until the late 1920s).

The 13 and 18 Pr guns were apparently introduced in 1904, but I’ve never seen a shell dated before May 1905, or a No. 80 Mk I fuze before 1906.

Graeme

 

[Alan1]

Graeme,
Mny thnks additional information, so much for my silver plating theory!
Grateful maker's name, was indistinct on both shell bodies, and I thought that there was another initial before the P. Now I know that there is not.
Hogg and Thurston give date of introduction of both guns as June 1904, and Parker gives 1905 as date for the No 80 fuze: no doubt there were trials etc etc before that, but, like you, I have never seen a shell dated before 1905. Parker also mentions the well-known reparation paid to Krupp for license fees due after the Great War.
Pure serendipity that these eg's happened to be preserved, even more serendipitous that I turned up before they were sea dumped and lost.
Alan1

 

[15 inch]

The 18Pr was in the 1904 LoC following trials on 24 guns made in 1903. Has anyone seen any of the cart cases or shells from the 1903 trials?

Production of the 18Pr commenced at the Royal Gun Factory with barrel serial number 25 dated 1905. This gun and carriage was in a batch that went to Australia in 1908. The barrel itself survives having been used as a fence strainer post on a wheat farm 100 miles east of Pert WA.

I have seen a similar example of a Schrapnel shell body the same as the one in the OP made in 1905. It looks like the fuze adapter ring was a slightly larger diameter than the later shells. Can that be confirmed?
cheers,
D.

 

[Darkman]

It looks like the fuze adapter ring was a slightly larger diameter than the later shells. Can that be confirmed?
cheers,
D.

The fuze socket adapter was, to some extent, custom made to match the shell. The final machining of the shrapnel shell nose profile was done with the adapter in place, and this lead to fairly large tolerance variations. Even the adapter outer thread diameters vary significantly.

I have a number of fuze adapters that I try to fit to a newly acquired shell to not only get to screw in, but to also match the mouth diameter. The variations are significant. Of course fired shells have varying degrees of distorted mouth openings, with the very early shells sometimes so expanded that the adapter threads won’t even engage the shell threads. But even unfired shells present a problem matching an adapter (if not present with the shell) due to the large manufacturing tolerance variations.

The worst example I ever had was finding an adapter to fit a fired but unoperated (dud) 1913 Mk III shell - the fuze and adapter had been removed sometime previously, but the pusher plate and some shrapnel balls were still inside. The shell mouth threads were extremely tight (small) and I couldn’t find an adapter that would screw in. After trying about 20 (including some from other complete rounds) I eventually got one to screw in very tightly, but I doubt it will ever come out again!

So my point is that shrapnel fuze socket adapters can vary significantly in outer diameter and thread diameter sizes - considerably more than the machining tolerances shown on the engineering drawings.

Graeme
(Ballarat, Vic)

 

[15 inch]

Graeme, thanks for that insight. I was wondering whether they were made that way, or whether the steel was softer or thinner in the early shells causing them to expand more. Later production shells don't seem to have the same issues, but as you say, the earlier ones were a bit more hand made. cheers, D.

 

[Darkman]

Early shrapnel shells (eg Mk I & II) had a very thin wall thickness near the mouth and expulsion of the pusher plate (larger diameter than the mouth opening) often caused significant distortion and bulging of the shell. The wall thickness was greater on later Mks but distortion was still evident to a degree. The Mk XII shell (late WW1) was completely redesigned to expedite the manufacturing process by reducing the pusher plate diameter to be less than the mouth opening (this meant the shell body didn’t have to be reheated and coned over by forging after the pusher plate and tin cup were inserted). The additional energy created by the pusher plate being forced out of a smaller diameter hole was compensated for by using a powder tin cup with a larger volume. So it’s usual to see Mk XII shells with a perfect original nose profile - as made - and the fuze socket adapters are generally a good fit.