I finally found & bought a 4 Bore rifle cartridge for my collection, in fact I could of had 2, this old Kynoch round & one of the later Aussie loaded cartridges, but I chose the Kynoch as more original & that is the brand I'm collecting if I can !

Now just need a 2 Bore then a 1 Bore Gatling round .

That's a 577/450 also by Kynoch for a size comparison