25 pdr shell base markings

[david moore]

Wonder if anyone can interpret the various markings on the two 25 pdr shell cases that I have. These were recovered by my father in January 1946 after the very large ammo explosion that took place at the Savernake ammo railhead in Savernake Forest, Wiltshire. These shells seem to have been fired - correct? So one wonders why they, as essentially recycle/scrap material were present with the trainload of live ammo? The trains were being loaded from the dump ready for disposal in the English channel.

[tankbarrell]

Top one is Canadian, Robert Mitchell/ Canada. Bottom one is British, Royal Laboratories Birtley. CF means cordite or charge full. Another F is stamped everytime a full charge is used. CR would mean charge reduced but that would not be used on 25 pr, usually used on an HE round in an anti tank gun.
Dates are self explanatory. Primer markings indicate maker and filling station

[david moore]

Thanks for the info Adrian. When you say that a new "F" was added at every refill, that presumably means that refilling was only done back at the munitions plant - and not in the field?

Again I could understand that live (refilled) shells would have been present in the ammo depot stores which, though "exploding" with the rest of the wagon loads, would show an unfired primer? These primers are "fired".

[tankbarrell]

Yes, refilling was not done in the field, cases have to be inspected, annealed and resized before re use.
I agree, the primers are fired, I can't answer your question about why they were there but they might have been near enough to live ammunition to be effected by an explosion or just abandoned at some point.

[CWO (ret) Gilles Aubé]

Hello everyone, Adrian Barrell mentions in his reply that the shell had to be resized.
Does someone know how this was done?
We have about 2 dozen oversize shells that we cannot use with our 3, 25 pdr guns.
Gilles

[rob love]

When I enlarge the first photo, it almost appears as though the primer is pierced and punched outwards, as opposed to the little dimple normally observed on a primer strike. Could the punchout be the result of a fire condition on an unfired primer?

I often will toss unfired but damaged small arms ammunition into the woodstove to make them safe for disposal. In all cases the primer is what pops out of the case. (note: The bullet does not whiz around the room killing everyone like you see in the movies).

[Lynn Eades]

Rob, please don't take this like Will Smith, but were the bullets in the fire anything do with your first wife heading out the door?
On the reloading thing, I would like to know the ins and outs of it. In hand sized fire arms. Military brass is usually harder than sporting ammo. Military ammo is usually sized smaller for auto loaders, For reloading, shells sometimes need annealing, Is this the case with reloading large shells? When are they scrap? In small stuff, shells get sized in a set of dies. I guess munitions factories use big gear to do the same stuff?
Waiting, Out!

[Mike Cecil]

David,

Work on the basis that the markings give enough information to trace each component back to source, so that any defects/defective parts can be traced by batch to the originating factory or filling station.

Primer markings have the date/manufacturer/type (eg No.1 or No.11 in the case of a 25-pdr)/date of manufacture, and a second set giving the filling station/date of filling/batch number.

Cart case is similar. At each refill, the first 'F' is struck out, and another F stamped adjacent. As Adrian said, CR is not applicable to the 25-pdr as it is a separate (not a fixed) round where the charge weight can be varied at the gun. AT rounds are 'fixed' and cannot be varied, hence any reduction in charge weight is done at the factory/filling station.

Cart cases are returnable stores, ie 'produce' where the spent primer is removed, the case cleaned, and then measured for wall thickness/length/ before annealing, full length resize in a die, length trimmed, checked for imperfections, then sent off to the filling station (or scrapped). With a 25-pdr, there was such a variety of charge weights that the stress on a cart case could vary greatly, so it was worth the trouble to return and if within tolerance, re-use.

Mike