Ammunition Makers: 155mm Shells and the Artillery War

What Defines This Group

This group is bound together not by a product line but by a single chokepoint: the 155mm artillery shell and the propellant that drives it. These are the firms that forge steel bodies, fill them with explosive, press propellant charges and pack complete rounds. Some, like Rheinmetall and BAE Systems, are large listed primes for whom munitions are one of several businesses; others, like Nammo and CSG, are munitions specialists where this is the core trade.

The table below compares the major Western players. Listed parents carry approximate market capitalizations with an as-of date; private and state-owned firms are framed qualitatively, since they have no public share price.

⚠ Caps are rounded approximations from public market-data aggregators and vary by source and date: Rheinmetall ~€56bn as of 14 Jun 2026 (companiesmarketcap.com); BAE Systems ~£63bn as of early 2026 (tradingeconomics.com); General Dynamics ~$92bn as of early June 2026 (stockanalysis.com). Nammo and CSG are private/state-owned and have no public market cap.

The 155mm Bottleneck

Artillery dominates casualty statistics in the Ukraine war, and the 155mm NATO-standard shell is its workhorse. At peak intensity Ukraine fired tens of thousands of rounds in a day, while Russia sustained even higher rates. The problem was supply: decades of post-Cold-War disarmament had left Western lines mothballed, with Europe and the United States together producing only a few hundred thousand rounds a year before 2022.

That mismatch translated directly into battlefield outcomes. Through 2023 and into 2024 Ukrainian units rationed fire, sometimes to a fraction of the Russian rate, and the shell ratio became a recurring theme in operational reporting. Politicians spoke of shells the way earlier wars spoke of tanks or aircraft — as the scarce resource that set the tempo.

The response was a generational industrial mobilization. Governments signed multi-year contracts, funded new plants and pooled money to buy rounds on the global market. The ammunition makers, long treated as a sleepy corner of defence, suddenly found their order books and share prices transformed.

Propellant: The Hidden Constraint

Headlines counted shell bodies, but insiders knew the real ceiling lay deeper in the supply chain. A complete round needs a forged steel body, an explosive fill such as TNT, a fuse and, critically, propellant to launch it. Forging empty bodies is comparatively quick; producing the energetics is not.

Propellant depends on nitrocellulose, and Europe historically imported more than 70 percent of its cotton-linter feedstock — the raw material for nitrocellulose — from China. When those deliveries tightened in 2024, assembly lines stalled. In one widely cited snapshot, a plant that forged around 40,000 shell casings in a month completed only about 18,000 finished rounds because of propellant and fuse shortfalls.

Switching to wood-derived cellulose is technically feasible but triggers lengthy safety recertification, since propellant formulations are treated as safety-critical and require stable specifications and repeated testing. TNT supply added a second chokepoint, with only a handful of qualified Western producers. The lesson was blunt: a country can build all the shell-body presses it likes, but without secured energetics the visible output stays capped.

Production Ramp 2022–2026

The scale-up has been real and rapid. Combined 155mm production across the EU, the UK and Ukraine is projected to reach roughly 2.8 to 3 million rounds annually by 2026, several times the pre-war baseline. Rheinmetall alone is targeting about 1.5 million shells a year by 2027 and has signalled deliveries of more than 2 million rounds to European customers by 2030.

New facilities anchor that growth. Rheinmetall’s plant at Unterlüss in Lower Saxony, coming online in 2026, is designed for up to 350,000 rounds a year, well above its original 200,000 plan, with further lines breaking ground in Lithuania and Ukraine. Its acquisition of Spain’s Expal added several hundred thousand rounds of annual capacity.

Parallel to factory expansion, the Czech ammunition initiative reshaped procurement. Launched in February 2024, it pooled allied funds to buy shells worldwide and route them to Ukraine; by late 2025 it had channelled several million large-calibre rounds, accounting for a large share of all the ammunition Ukraine received. In the United States, the Army pushed toward a 100,000-round monthly target with GD-OTS and other contractors, though interim goals slipped under energetics and workforce constraints.

Rheinmetall, BAE, Nammo, GD-OTS, CSG

Rheinmetall emerged as the war’s defining defence-industrial winner. Its market value multiplied as it converted civilian sites — including a former Berlin auto plant repurposed for shell casings — and built what it bills as Europe’s largest 155mm plant in barely fifteen months. With roughly €56bn in market capitalization in mid-2026, it sits among the largest defence firms in the world.

BAE Systems, valued near £63bn, runs munitions and energetics on both sides of the Atlantic through its Land & Armaments arm, supplying UK shell and propellant lines and a significant slice of US energetics. It pairs deep munitions expertise with platforms, ships and electronics, giving it diversified resilience.

Nammo, the Nordic specialist owned equally by the Norwegian state and Finland’s Patria, punches above its size in propellant and ammunition. It has restarted shuttered lines, including a Danish plant, and repeatedly warned that without long-term contracts the industry could over-extend. GD-OTS, part of New-York-listed General Dynamics (~$92bn), is a pillar of the US artillery base, producing metal parts and running load-assemble-pack operations central to the American 155mm ramp.

CSG and its Excalibur Army subsidiary turned Czechia’s legacy arms expertise into strategic leverage. As privately held firms they publish no market cap, but they became central brokers and producers for the Czech initiative, sourcing and refurbishing shells from around the world and channelling them to Ukraine at scale.

Risks and Outlook

The central question for ammunition makers is durability of demand. The post-2022 boom rested on the assumption of sustained, multi-year orders, and firms invested billions in plant on that basis. A negotiated ceasefire, a shift in Western political will, or a pivot of funding toward drones and missiles could leave expensive new capacity underused.

Input security is the second risk. Expanded assembly lines mean little if nitrocellulose feedstock, TNT or skilled chemical-plant labour remains scarce. Reshoring propellant precursors is under way but slow, and a single chokepoint — a feedstock embargo, an explosion at a key plant — can throttle otherwise healthy output.

For now the trajectory points up. Long-term framework contracts, a maturing Czech initiative and competing US, German and Nordic capacity suggest Western 155mm output will keep climbing into the late 2020s. Whether that proves a wartime spike or a permanent rebasing of Europe’s defence-industrial base is the open question these companies — and their investors — are now wagering on.