I won a lot at an auction recently and part of the lot were quite a few original and collectible British cartridges.
Among them were these gems.

Eley 8bore, 700NE, 600NE, and a nice 577 Rewa.
The Rewa may even be a very rare original from 1930! To the best of my knowledge (very little) the original run from Kynoch had the “K” stamp. Hoyem says that none of the originals survive (that I would think went with the rifle to Martand Singh).
There were also many good examples of other BP and nitro cartridges which I will show off later as I go through them.