Ukraine-Nammo 155mm HE-ER Joint Production: Range-Extended Artillery in Country

Technical Summary

Ukrainian President Volodymyr Zelenskyy confirmed on 10 May 2026 that Ukraine and Norway will jointly produce 155mm extended-range artillery natures in country, building on a strategic cooperation agreement between Norwegian energetics and ammunition producer Nammo AS and an unnamed Ukrainian state defence enterprise. The natures to be produced are described in open reporting as based on Nammo’s 155mm High-Explosive Extended-Range (HE-ER) family and on the US-design 155mm M549A1 Rocket-Assisted Projectile (RAP).

The Nammo HE-ER round is currently produced in two principal variants: a base-bleed configuration delivering reported range of approximately 41km from an L/52 barrel, and a non-base-bleed extended-range design at approximately 34km. Both reportedly carry 9–10kg of high-explosive filler (composition not disclosed by Nammo in open material; on type analogy with most Western HE natures, likely Insensitive Munition Explosive (IMX) or TNT/RDX-based fill such as Composition B). The M549A1 RAP carries a small rocket motor in the base, extending range from a 155mm L/39 barrel (M109A3GN) to approximately 30km, against the standard M107 HE round’s 14km from the same platform.

Analysis of Effects

For Ukrainian counter-battery operations the strategic logic is straightforward. Russian 152mm 2S19 Msta-S and 2A65 Msta-B fires reach approximately 24–29km with standard HE-OF, extending to ~40km with Krasnopol-M or rocket-assisted natures. A Ukrainian artillery battery firing HE-ER base-bleed from an L/52 barrel (PzH 2000, CAESAR Mk II, Krab) can sit outside the engagement envelope of a Russian 2S19 firing OF-540, and engage Russian counter-battery radars and command posts at 35–40km. The M549A1 RAP variant addresses the legacy Norwegian-donated M109A3GN fleet which retains the shorter L/39 barrel and cannot exploit the full HE-ER envelope.

For ammunition technicians the more interesting question is what “joint production in Ukraine” actually means in practice. The HE-ER projectile body, the base-bleed unit, the explosive fill, the fuze pocket, and the booster are each separately manufactured items with separately governed In-Service Surveillance (ISS) regimes under STANAG 4527 and related publications. Press reporting to date does not distinguish which sub-components will be Ukrainian-produced and which will continue to come from Nammo’s Raufoss or Karlskoga facilities. The plausible near-term configuration is Ukrainian projectile body and assembly with Norwegian-supplied energetics — explosive fills, base-bleed propellant, and base-bleed igniter — reflecting Ukraine’s rapidly maturing forging and machining capability but still-limited domestic energetics base.

The Hazard Classification implications for Ukrainian transport and storage are non-trivial. HE-ER stores typically carry UN HD 1.1 D for the complete round (with separate HD 1.4 S or 1.4 G classifications for the base-bleed igniter), and quantity-distance (QD) calculation in Ukraine’s wartime storage estate must reflect both the projectile NEQ and the base-bleed energetic mass. STANAG 4439 IM classification of the produced rounds will determine whether the Ukrainian production runs can be stored alongside legacy Soviet-pattern stocks or whether segregated storage facilities are required.

Personnel and Safety Considerations

EOD and Ammunition Technician implications: (1) An Increased prevalence of base-bleed and rocket-assisted natures in Ukrainian inventory means an increase in dud rounds containing residual base-bleed propellant or unfired rocket motors. RSP planning must address motor case integrity and propellant grain stability under field conditions. (2) Mixed Western and Soviet-pattern 155mm/152mm ranges create scope for nature-misidentification under recovery operations — visual differentiation aids and radiographic libraries should be updated. (3) The base-bleed igniter is a separate ammunition store with its own hazard properties; logistics staff should not assume issue-state HE-ER rounds carry the igniter pre-installed. (4) Long-term: where Ukrainian production diverges from Nammo type-certification baselines, parallel ISS regimes will be required to validate Ukrainian-fill rounds independently of the Norwegian-fill type record.

Data Gaps

DATA GAP: identity of Ukrainian state defence enterprise partner not disclosed; production location in Ukraine not announced; first-delivery date not specified; planned annual production rate not stated; explosive fill chemistry not confirmed by Nammo (IMX-101, IMX-104, or Composition B all plausible); NEQ per round not stated in open source; STANAG 4439 IM classification not announced; M549A1 production tooling source and US-government technology transfer authorisations not described; price per round not disclosed; whether base-bleed unit will be Ukrainian or Norwegian produced not clarified.

AI-assisted technical assessment based on open-source material. Not a formal intelligence product. Source ratings (NATO STANAG 2022): Office of the President of Ukraine (B-2 — official statement, single-source for production decision); Ukrinform/Defence-UA (B-2/B-3); Militarnyi/UNITED24 (C-3, regional defence trade reporting). Nammo product literature consulted for HE-ER baseline specifications.