Spanish shotshells from the '20s.
The box mention “Taller de carga de cartuchos” = Cartridge loading workshop, but it doesn’t say where the shop was. We know there was an UEE shop in Madrid.
The cartridges were loaded using Orbea cases and primers, or better primed cases, with brass-washed iron heads. Anyway, UEE also loaded shotshells with their own headstamp. I don’t know if these with Orbea components were a special line of higher quality. The UEE shotshells I have seen are of the low brass head type and of worse appearance.
The HO monogram stands for “Hijos de Orbea” (Sons of Orbea). This firm was founded in 1926 in Vitoria, in the north of Spain, and as far as I know, they’re still in business.
These shotshells were loaded with Diamond smokeless powder. This Diamond brand was popular for reloading at the time too, and it made black powder also. I haven’t been able to find who the maker of this Diamond powder was.
What was the denomination of this one-piece shotshell primer? Are they made still nowadays? It seems that everybody makes the battery-cup type now.