Cap tin for Joyce's central fire cartridges

I assume the ‘Joyce’s central-fire cartridges’ referred to on this label are shotgun shells. Anyone have any information on these?

Joyce also manufactured .320, .380, and 410 Revolver or at the very least had them made with a F. J. headstamp. So these could be for those? Or for shot gun shells.
The outer blue & gold paper wrapper appears to be the same as found on Eley Colt tins.

Pete,
I hadn’t considered the Joyce metallics, but would expect these to be in smaller tins. It would be nice to see how large the primers in this tin are.

[quote=“Guy Hildebrand”]Pete,
I hadn’t considered the Joyce metallics, but would expect these to be in smaller tins. It would be nice to see how large the primers in this tin are.[/quote]
Guy, have the tin ex-rayed and, you will get an idea as to size. M. Rea

Unfortunately, the tin is not mine; otherwise, I could carefully remove the wrapper and take a look at them. The owner has sent me a picture of a couple of the primers, but with no dimensions. They appear to essentially be long percussion caps, but lacking the grooves in the sides that percussion caps typically have.