If it is Swiss made, it should be manufactured by RUAG, they are a big player and GTG.
From the German Wikipedia:
In 1995 the two ammunition factories were merged into the SM Swiss Munitionsfabrik and in 1998 it was transferred to RUAG (with the division designation RUAG ammunition), a private limited company, together with the other dependent public-law federal armaments companies.
German line [edit | Edit]
The German Rheinisch-Westfälische Explosives AG (RWS) was founded in 1886 and later expanded to Nuremberg and Fürth. In 1889 RWS took over the ammunition factory of Mr. H. Utendoerffer in Nuremberg and in the following years built a munitions factory in Stadeln / Fürth. The dynamite AG, formerly Alfred Nobel & Co merged 1931 u. a. with the RWS to the new Dynamit AG with head office Troisdorf. At the beginning of the 1960s, the company trading under Dynamit Nobel AG took over Gustav Genschow & Co, founded in 1912. AG (GECO) from Karlsruhe and 1990 the Swedish Norma, which produced since the beginning of the century.
2002 - today [edit | Edit]
In 2002, RUAG took over the small-caliber ammunition production business from Dynamit Nobel AG in Germany and thus expanded its own production portfolio. The new business unit was named RUAG Ammotec. In the following year, RUAG Ammotec took over the distribution and trademark rights of the civilian ammunition from the Austrian Hirtenberger AG and five years later the MFS 2000 in Syrok, in the north of Hungary. Since 2009, RUAG Ammotec has also been producing in Tampa (USA) and now in five countries.
The other areas of the RUAG ammunition, which were the production of Grosskalibermuntion (artillery and mine throwers (mortars)) and shaped charges, were initially run separately under the old name RUAG ammunition and then sold for lack of market opportunities to Saab Bofors Dynamics. The metalworking, metal components and recycling businesses in Altdorf were separated and taken to RUAG Components (later RUAG Technology).
Products [edit | Edit]
Army and authorities [edit | Edit]
In addition to the German Armed Forces, the Swiss Armed Forces and the armed forces of various NATO members, police forces in various countries, for example, are also customers of RUAG Ammotec. In addition to the production of ammunition up to the caliber 12.7 mm also defensive, offensive and practice hand grenades are produced.   Other products include the Swiss Ordonance Cartridges GP 11 and 5.6 mm Gw Pat 90 (standard ammunition in NATO caliber 5.56 mm, adapted to the Swiss assault rifle 90) and the sniper line "Swiss P".
Hunting and Sport [edit | Edit]
The RWS, Rottweil, GECO and Norma brands cover all applications of shotgun, rifle, edge and centerfire cartridges.
Their USA webpage