Illustrative image. Polish Land Forces AHS Krab self-propelled howitzers fire during Iron Defender-25 at Orzysz Training Area, Poland, 17 September 2025. The Krab is one of the two platforms the new projectile is designed for, but these are not the rounds or the firing described in this article. U.S. Army photo by Pfc. Andre Gremillion Jr, VIRIN 250917-Z-PV485-1069, released via the Defense Visual Information Distribution Service. U.S. Government work, public domain. Use does not imply endorsement by the U.S. Department of Defense.

Thirty Kilometres and No Gas Generator: Poland Fires Its First Nationally Designed 155 mm Projectile

On 2 September 2026 the Military Institute of Armament Technology (WITU), PGO S.A. and Niewiadów Polska Grupa Militarna fired the first integrated 155 mm projectile of wholly Polish design at the Central Air Force Training Ground at Ustka. The round is a hollow base nature with no gas generator fitted. The first shot exceeded 30 km and later series averaged safely above 30 km. The published design target is 30 km hollow base and more than 40 km with a gas generator.

Technical Summary

The firing took place on 2 September 2026 at the Central Air Force Training Ground at Ustka on the Baltic coast, with the Polish Navy securing the range and several dozen WITU personnel supporting the trial. A series was fired shortly after 11:00 local time from a 155 mm self-propelled howitzer released specifically for the test. The partners report that the first shot exceeded 30 km at high velocity with stable pressure parameters, and that subsequent series returned an average safely above 30 km. Range, dispersion and correct functioning were the three things under examination.

That is the whole of the news, and it needs separating from what sits behind it. The round is a Hollow Base nature, meaning a cavity formed in the projectile base rather than a gas generator, and the next milestone the partners name is an analysis of whether to fit a base bleed unit. The published design target is 30 km with the hollow base and more than 40 km with a gas generator, on a projectile carrying about 10 kg of explosive and compatible with the two 155 mm platforms Poland already fields, the AHS Krab and the Korean K9. Ustka has met the first half of that target. PGO puts the estimated capacity of its cast body route at about 100,000 bodies a year and says commercialisation is possible in 2027. The projectile goes on the company stand at the International Defence Industry Exhibition in Kielce this week, from 8 to 11 September.

Subsequent series confirmed an average range safely above 30 km, demonstrating the repeatability and stability of both the concept and the design. PGO S.A. and Niewiadów Polska Grupa Militarna, joint statement, 2 September 2026

What “First” Means Here

Precision matters on the word first, because the partners are claiming something narrower than the headlines suggest and the narrower claim is the interesting one. Poland has been turning out 155 mm ammunition for years. MESKO has been making projectile bodies at Kraśnik under a Slovak licence since 2023, Dezamet assembles the complete round and produces the fuze under licence, and Nitro-Chem fills it. What did not exist until 2 September was an integrated 155 mm projectile of Polish design, fired as a projectile, with the design authority held in Poland and no licence sitting on top of it. Nor is this the only Polish attempt at that. WB Group is running an entirely separate indigenous family of high explosive hollow base and high explosive base bleed natures, with its own gas generator already reported through bench testing, and certification targeted for this month. There are three tracks here, not one, and reading Ustka as the whole national story flattens the picture.

What the Ammunition Set Actually Contains

A 155 mm round is not one item. The Military Institute of Armament Technology defines a set as the explosive filled projectile with its fuze and an optional base bleed unit, a set of modular propelling charges, and an igniter. The table below covers every element of that set for which a Polish producer is on the open record, with the status of each as at 8 September 2026.

What Is Still Missing

The same population, read the other way. These are the remaining elements and determinations where Polish capability or programme status is not publicly documented.

On “not publicly documented”. The entry records the state of the open source record and nothing more. It does not mean a capability is absent, a test has failed or a decision has gone against the programme. Qualification files, hazard classification records and insensitive munitions assessments are held in registers that are not open to the public, and a company is under no obligation to announce a supplier. Absence of a public entry is a finding about the record, not about the capability.

Why the Money Is There

The driver is contractual rather than aspirational. In December 2023 the PGZ-Amunicja consortium and Poland’s Armament Agency signed an agreement worth close to PLN 11 billion for ammunition set deliveries to the Polish Armed Forces between 2024 and 2029. A second implementation agreement followed on 30 May 2026, worth more than PLN 13.5 billion for several hundred thousand artillery ammunition sets, financed under the European Union SAFE programme. In July 2025 the Polish Capital Investment Fund allocated more than PLN 2.4 billion to four companies in the Polish Armaments Group to expand 155 mm production, of which Zakłady Metalowe Dezamet received PLN 1.36 billion, MESKO PLN 887 million, Nitro-Chem PLN 113 million and ZPS Gamrat PLN 66 million.

The demand side is the reason those numbers keep rising. WITU’s own published assessment puts Polish contracts with domestic industry and with South Korean suppliers at more than 400,000 ammunition sets, against a force that is contracted for 364 K9A1 and K9PL howitzers and 186 Krab and Krab 2 units, with 26 Krabs delivered before the war. On WITU’s reading, supplying that force for training and an initial wartime reserve needs on the order of one million sets, and wartime consumption for a force of 800 to 1,000 systems would run into the millions a year. Those are the institute’s figures and its assumptions, and they are the reason a second source for something as unglamorous as a shell body is being treated as strategic. Read them as the institute’s figures at the date of its publication rather than as a standing Ministry of National Defence requirement, and expect the platform counts to be overtaken by later executive contracts. ISC covered the fuze component half of the same problem in our August analysis of the Dezamet fuze pyrotechnics agreement.

Two developments on the same industrial map are worth putting alongside the Ustka firing. On the very day the projectile was fired, Hanwha Aerospace Europe announced that a test group appointed by the head of the Armament Agency had completed verification of the K-MCS modular propelling charge in the Republic of Korea with a positive result, which means Korean-supplied ammunition for the K9 fleet will come with those charges. A body and a charge are two halves of the same set, and the charge half moved that day too. Separately, Northrop Grumman and Elaboracja Niewiadów have signed a memorandum of understanding to explore collaboration on 155 mm ammunition for Poland, including the potential delivery of austempered ductile iron shells, which puts a second industrial partner behind the cast body route.

Analysis of Effects

Read the milestone language rather than the headline number, because the sequence tells you where this design actually sits. A spin stabilised artillery projectile in supersonic flight loses energy to three things: wave drag at the nose, skin friction along the body, and base drag from the low pressure wake behind a blunt base. Artillery has three established answers to the third of those. A boat tail reshapes the base to narrow the wake. A base bleed unit burns a slow propellant grain and injects gas into the wake to raise base pressure, which is the standard route from a 30 km class round to a 40 km class round. A rocket assisted projectile adds thrust and pays for it in payload volume. A base cavity, which is what Hollow Base describes, is the passive option: it changes the base geometry and the mass distribution without carrying any energetic material aft of the bursting charge. What Poland has proved at Ustka is the passive case. The partners have said in the same breath that the gas generator is still under analysis, which is a precise way of saying the extended range variant does not yet exist. ISC reads the sequencing as deliberate rather than incremental. A base cavity is also a volume, and a volume in the base of a projectile is where a base bleed grain goes. Proving the passive body first, then fitting the generator, keeps the bursting charge cavity and the body geometry fixed across both variants. That is the reading the partners' own milestone language supports, and it is an inference from their sequencing rather than a design statement any of them has published.

A range figure without the gun that fired it is not a specification, and the gun has not been identified. Range on a conventional projectile is set by ordnance length, charge zone, projectile mass and the muzzle velocity those produce, and none of the four has been published for this trial. The reference frame for the comparison is the NATO 155 mm/52 convention, the 23 litre chamber arrangement that sits behind the interchangeability procedure in STANAG 4425 and Allied Ordnance Publication AOP-29 Part 1, and behind the Joint Ballistics Memorandum of Understanding signed by the United States, France, Germany, Italy and the United Kingdom. For an indicative scale on a different weapon with different ammunition, the published figures for the Patria 155 GH 52 APU towed howitzer are 31.7 km with a standard projectile and 41 km with a base bleed projectile. Treat that pair as a scale and nothing more, because published range figures for any gun move with the projectile fired. Set the Ustka result against it and the reading is straightforward: above 30 km with no gas generator puts the Polish round in the conventional class for an L52 ordnance, and the base bleed decision is the one that would move it into the other class. Both target platforms carry L52 ordnance, so the frame is the right one even though the trial gun is unstated. One caution on the word compatible. A NATO standard projectile can be fired from NATO standard guns, but each nation still has to qualify it on each weapon for performance and safety. Compatibility with the AHS Krab and the K9 is a design aim here, not a completed determination on either.

Personnel and Safety Considerations

A projectile body is not a munition. It becomes one when it is filled, fuzed and assembled to a charge, and each of those steps carries its own safety and classification consequence. The Ustka rounds were described as integrated, which means a fill and a fuze were present, but neither has been publicly identified for the rounds fired. The design target published for the projectile is about 10 kg of explosive, which is a design figure for the nature and not a net explosive quantity measured or declared for the rounds on the gun that day. A filled 155 mm high explosive projectile with a bursting charge is conventionally consigned as UN 0168, Hazard Division 1.1, Compatibility Group D, and the assignment is made by test under the procedures in STANAG 4123 and Allied Ammunition Storage and Transport Publication AASTP-3, using the United Nations Test Series 6. That assignment then drives everything downstream: quantity distance under AASTP-1 Edition D Version 1, dated November 2025, mixing and storage rules by compatibility group, and the net explosive quantity licensed at each site. No hazard classification has been published for this nature, and the Polish classification record is not an open register, so the absence of a public entry is a fact about the open source record rather than about the programme. Two further qualification questions are unanswered on the same basis. Qualification of the explosive fill runs through STANAG 4170 and AOP-15. Insensitive munitions assessment runs through STANAG 4439 and AOP-39, and it matters here because a new body geometry, a base cavity and a later gas generator each change the response of the assembled round to fast and slow heating, bullet attack and fragment impact. A base bleed unit in particular adds a second energetic composition inside the projectile, aft of the bursting charge, and that is a materially different insensitive munitions case from the one tested at Ustka. On the range itself, the sea danger area at Ustka and the Polish Navy's role in securing it are the visible part of a firing safety case for a projectile whose ballistic behaviour was, on the day, being measured rather than assumed. Downstream of the trial the storage arithmetic is already moving: Niewiadów currently holds seven specialist storage facilities of about 3,900 square metres in total, and the expansion under way is intended to take licensed capacity above 500 tonnes net explosive quantity. That is the number a quantity distance calculation is run against, and it grows with the production rate rather than with the range figure.

Data Gaps

The self-propelled howitzer used at Ustka is not identified, which leaves ordnance length and therefore the ballistic frame unstated. No charge system or zone is named for the range firing; the enhanced TCS charge appears only in the late August body strength check at Niewiadów, and the expansion of the TCS designation is not in the open record. Projectile mass, muzzle velocity, chamber pressure and drag coefficient are unpublished, as is the dispersion result, even though dispersion was one of the three parameters under test. The explosive fill type is unstated and the published figure of about 10 kg is a design target for the nature rather than a declared net explosive quantity for the rounds fired. The fuze fitted at Ustka is not identified; the WITU plan of record names the KZ984 fuze produced under licence by Zakłady Metalowe DEZAMET, but no source ties it to this trial. The two company accounts of the earlier test sequence differ, and neither identifies the Ustka howitzer. Hazard division and compatibility group are unpublished. No insensitive munitions assessment, ballistic interchangeability determination or Introduction to Service decision has been published. It is not stated whether a future base bleed unit would come from the WITU design under development at Zielonka or from the ZPS Gamrat line at Jasło. Finally, no contract, schedule or unit price for series production has been announced; commercialisation is stated as an objective, not as an award.

Editorial responsibility. This analysis is researched, written and published under the editorial responsibility of Steve Sawyers, MIExpE VR. Every technical claim is sourced to named open-source material and rated for reliability and accuracy under NATO STANAG 2022. ISC uses its own domain-trained research and drafting system under human direction; the analysis, the judgements and the accountability for them are ours. Corrections and updates welcome: if you hold open-source data that refines or corrects any parameter here, write to [email protected] citing the specific claim and your source. Verified corrections are incorporated and credited in the revision history. Full editorial and AI policy.