Sellier & Bellot were two Frenchmen who, having gained a Licence from the Emperor of Austria, set up a Musket percussion cap factory in Prague (Bohemia) in 1823, to supply both Military and Sporting caps to the newly introduced ignition system.
By the 1870s, the prague factory was making all sorts of Military and Sporting metallics, Percussion Caps and Primers, and related items.
After WW I, and the Independance of the Czechoslovak area of the Empire into its own republic, S&B expanded with a new plant at Vlasim, about 60km south of prague, in a heavily wooded area, ideal for an Amnmunition factory.
The Prague factory continued production for some time, even after Vlasim was well under way. The Prague factory concentrated on Pistol ammo during the latter years of its functional life.
S&B maintained its main (sales) offices in Prague ( where they are still nowadays,) whilst its main operations of research and manufacture are all at Vlasim.
The SBP headstamp derives from the times when S&B had several factories around Europe before and after WW I (Schoenebeck am Elbe, Riga, and Prague, as well as Vlasim); After WW II, only the Vlasim factory remained, Prague having been reduced to a mere sales office, and the other factories having been destoryed or taken over by new regimes.
S&B maintained the SBP mark on a lot of ammo(mostly Pistol) even though the ammo itself was all made in Vlasim, after WW II; maybe to maintain “Brand Loyalty” in pre-war markets, such as Latin America…Spanish and English are the two main foreign languages of the Sales staff and office receptionists at S&B’s Prague office, whilst German and Russian predominate amongst the Vlasim engineering staff ( and nowadays, English naturally.)
It was fun in 1993, arranging the details of an already-approved visit in Spanish, with some English thrown in,with the office staff; then discussing technicalities with Older Engineering staff at Vlasim in a mixture of German, English and the occasional Russian ordnance term thrown in… One of the senior engineers had started in 1944-45, under German Control, and was still there in 93, acting as a senior “elder” consultant in ammo manufacture, especially steel case technology…what a mine of info. (not only the cartridges, but the machines to make them as well…S&B makes a lot of its own machinery, or re-builds ZB and German equipment as well.).