Diehl and Nammo open 155mm shell production in Bavaria

German defense group Diehl has opened a new production line for 155mm artillery shell bodies at Röthenbach an der Pegnitz in Bavaria, built with help from Norwegian ammunition maker Nammo.

Diehl Metall and Diehl Defence inaugurated the line on November 10, the companies said. Pilot-series production began in October.

The line makes the steel bodies for DiNa, a 155mm artillery round developed by Nammo. Diehl and Nammo have worked together on the round since 2019 through a joint venture, ARGE DiNa, which focuses on the German market. Germany and other partner nations can order complete DiNa rounds and components under existing framework agreements.

Diehl started the project in June 2024, after receiving what it called the largest artillery ammunition order in Diehl Defence’s history. The company converted an existing production hall of about 7,000 square meters (75,000 square feet) instead of building a new plant, which let it start production in a little more than two years. Diehl put the investment in the mid-double-digit millions of euros.

Diehl and Nammo executives join German and Norwegian defense officials at a ribbon-cutting ceremony for expanded 155mm ammunition production. Photo by Diehl Defence

The new equipment covers the full process of making a shell body: forming, welding, machining, surface treatment and testing. At its center are two new forging presses, which shape heated steel into the hollow bodies that are later filled with explosives and fitted with fuzes.

The work is split among three partners. Diehl Metall, the group’s metal-forming business, makes the shell bodies from start to finish. Diehl Defence sets the quality and system requirements and takes the finished bodies into its ammunition production. Nammo provides the technology transfer and production know-how.

“This project thrives on the collaboration between our companies. Diehl Metall, Diehl Defence and Nammo each contribute their respective strengths and share responsibility for delivery,” said Helmut Rauch, CEO of Diehl Defence.

The plant is also a shift for the site itself. Most of the workers on the new line previously made synchronizer rings, a car gearbox component, and are being retrained for ammunition work. Diehl is also hiring additional skilled staff.

“Delivering the defence capabilities needed for Europe requires a strong defence industrial base and close cooperation across industry,” said Morten Brandtzæg, president and CEO of Nammo.

The 155mm shell is NATO’s standard artillery round, and demand for it has surged since Russia’s full-scale invasion of Ukraine. European governments have sent large quantities from their own stocks to Ukraine and are now paying to rebuild their reserves, which has pushed manufacturers across the continent to add capacity. Nammo has also worked on longer-range 155mm ammunition, and the U.S. Army adopted a European shell that hits targets 43 miles away.