NATO 35 mm × 228: Three Production Hubs Stabilise a Caliber Long Treated as Niche

For most of the post-Cold-War period the NATO 35 mm × 228 caliber sat in a single-supplier risk hole. Rheinmetall Air Defence (formerly Oerlikon Contraves) in Zürich was the de-facto monopolist, and when its dedicated 35 mm High-Explosive Incendiary-Tracer (HEI-T) line went dormant several years before 2023 the alliance had no obvious second source for an ammunition family used by every Gepard, Skyguard, Skyshield, MANTIS, Skyranger, Millennium, Bushmaster III and Oerlikon GDF mount in inventory. The picture in May 2026 looks different.

NAMMO Palencia delivers 35 mm HEI-T with Self-Destruct (SD) at roughly €350 per round to the Spanish Ministry of Defence under an active Allied Quality Assurance Publication (AQAP) 2110 baseline. Rheinmetall's 35 mm × 228 line at Unterlüß in Lower Saxony has been live again since spring 2023, against the February 2023 German MoD order for 300,000 Gepard rounds for Ukraine; the broader Unterlüß ammunition plant inaugurated on 27 August 2025 has since scaled that capacity alongside a new 155 mm artillery hub. Türkiye produces the Oerlikon KDC-02 under licence by Makina ve Kimya Endüstrisi (MKE) and has fielded two indigenous platforms (Aselsan's KORKUT and the MKE-led TOLGA), while MKE Kırıkkale itself manufactures the ATOM programmable airburst round and a new Fragmentation Anti-Drone Ammunition family.

The producer base for conventional 35 × 228 HEI-T and TP-T extends further. MESKO (Skarżysko-Kamienna, Poland; Polskie Grupy Zbrojeniowe) runs an active FAPDS-T and TP-T line for the Polish Armed Forces. ROMARM (Bucharest; exports through ROMTEHNICA) publishes its own 35 × 228 datasheet. Poongsan Corporation in the Republic of Korea supplies medium-calibre rounds across an extensive US export book. Production capacity, export rights and gun-specific qualification operate as three separate constraints, and Section 10 treats each in turn.

One gun lineage. At least seven manufacturers. Two consumer platforms shaping the export market in 2026. That is the shape of NATO 35 mm × 228 today.

The operational driver behind the reset deserves a sentence of its own. The renewed alliance interest in 35 × 228 is not industrial diversification in the abstract. It is a direct response to the cost-exchange problem that drone swarms, FPV loitering munitions and rocket-artillery-mortar (RAM) projectiles have created against more expensive air-defence layers. A 35 mm KETF round costs the high three figures in US dollars and engages a Class 1 or Class 2 UAS at 1–4 km with one or two-burst probability of kill in single digits to low tens. The next layer down (a Mistral or Stinger surface-to-air missile) costs in the tens of thousands of dollars per round. The next layer up (a Patriot or Aster shot) costs in the millions. For the saturated low-altitude threat band the 35 mm calibre defines the cheapest hard-kill solution NATO has, and the demand that creates is the gravitational field everything in this article is responding to.

For the baseline numbers: a 35 × 228 complete round masses approximately 1.56–1.58 kg. Standard HEI-T leaves the muzzle at around 1,175–1,180 m/s. Projectile masses sit in the 535–565 g band across NAMMO, Rheinmetall and MKE production. KETF rounds are heavier (~750 g projectile total) and slower (~1,050 m/s) because of the sub-projectile payload geometry.

Section 1
Why the Swiss line went dormant, and why Spain did not wait

Restarting a dormant ammunition production line is not a procurement decision; it is a regulatory re-authorisation. AQAP-2110 Edition D Version 1 (2016), the workhorse NATO Quality Assurance publication for design, development and production, requires a manufacturer of a previously-cancelled product to reconstruct the full Technical Data Package (TDP), re-validate every process step, retrain and re-certify personnel, fire a new qualification lot through ballistic, environmental and Insensitive Munitions (IM) testing, and clear multiple Government Quality Assurance (GQA) approval gates. Industry estimates put first qualified delivery from a cold start at 24 to 36 months.

Spain looked at that timeline and the unit cost, Rheinmetall's open-source HEI-T pricing under the 2023–2024 Ukraine framework sits in the €390–550 per cartridge range (the 2023 mixed-lot of 300,000 APDS-T + HEI-T at €168 million blends to €560/round, but the December 2024 HEI-T-only contract for 180,000 rounds at a "high double-digit million" sum disaggregates to roughly €440–525 per cartridge), with the Advanced Hit Efficiency and Destruction (AHEAD) / Kinetic Energy Time-Fused (KETF) variants past USD 750, and went to NAMMO. The Palencia plant in Castilla y León already held an active medium-calibre AQAP-2110 baseline, Spain still operated Oerlikon 35/90 KDB gun mounts that NAMMO could use as the qualification asset, and the national Government Quality Assurance Representative (GQAR) could certify the product under STANAG 4107 without an external sponsor. The result, captured in the 2024 NAMMO Ammunition Handbook, is a 35 mm HEI-T/SD cartridge described as "supplied to Spanish MoD for 35 mm Oerlikon KDB gun", a discreet entry that masks a strategic re-sourcing.

The technical comparison is unremarkable in the way a successful second-sourcing should be:

Source ratings (NATO STANAG 2022): NAMMO Ammunition Handbook 2024, B-2. Rheinmetall Gepard contract pricing, B-3. AHEAD pricing range, C-3. ISC's reading is technical equivalence with a marginal performance edge on projectile mass, delivered at roughly 60% of the alternative unit cost.

Section 2
Rheinmetall rebuilds at Unterlüß, 2023 restart, 2025 scale-up

The Rheinmetall response to the Swiss-line dormancy began earlier than the headline 2025 plant opening suggests. The 35 mm × 228 line at Unterlüß in Lower Saxony was reactivated in spring 2023, against the February 2023 German Ministry of Defence contract for 300,000 rounds (150,000 APDS-T plus 150,000 HEI-T) for Ukrainian Gepard self-propelled anti-aircraft guns. The first 40,000 rounds of that order were delivered to Ukraine in September 2023. A follow-on order in December 2024 added 180,000 HEI-T rounds at a reported "high double-digit million" euro value, with delivery commencing in 2026.

On 27 August 2025, Rheinmetall inaugurated the broader Unterlüß ammunition complex. The €500 million investment focuses primarily on a new 155 mm artillery hub, configured as two main buildings: one for projectile-shell production, one for loading, assembly and packaging, with up to 350,000 artillery shells annually at full capacity from 2027. The 35 mm line had by then been live for over two years. The new complex extended capacity; it did not initiate it. ISC's earlier framing of August 2025 as "the primary European hub" overstated the discontinuity. The accurate reading is that the 35 mm line was rebuilt for Ukraine in 2023 and the 2025 inauguration extended the surrounding industrial footprint.

Source ratings: 27 August 2025 Rheinmetall press release on the plant opening, A-1 for existence and scale; B-2 for capacity projections (industry-supplied, not independently audited). February 2023 German MoD order and September 2023 first-delivery confirmation, A-2 (multiple trade-press and Rheinmetall confirmations).

Section 3
Türkiye's licensed extension, and MKE as the fourth hub

The third production geography is Türkiye, and it sits in a category of its own. Türkiye now fields two distinct 35 mm gun designs. The Oerlikon KDC-02, the late single-feed variant of the Oerlikon-Contraves Mk 323 design, is produced under licence by MKE and equips the KORKUT SPAAG, the GOKDENIZ naval close-in weapon system, and the GDF-003B towed mount (the local designation for a modernised GDF-003-class system). Alongside it, MKE has developed an indigenous 35 mm Revolver Gun with a five-round drum that goes to 1,500 rounds per minute (adjustable from 1 to 1,500 rpm). First exhibited as a full-scale mock-up at SAHA EXPO 2024 and at IDEF 2025, this is the gun inside the TOLGA SHORAD fire unit. The associated airburst rounds are marketed by MKE under the ATOM designation. They function as Kinetic Energy Time-Fused (KETF) cartridges in the same family as Rheinmetall's Advanced Hit Efficiency and Destruction (AHEAD), ejecting a pattern of tungsten sub-projectiles ahead of the target along a programmed trajectory.

The Oerlikon Mk 323 family covers three guns: the belt-fed KDA (Gepard, Type 87), the early KDB (GDF-001 and GDF-002 towed mounts), and the linkless KDC (GDF-003 and GDF-005 towed mounts, plus the naval KDC-01 in Millennium predecessors). Of those three, only the KDC can host the inductive muzzle programmer that AHEAD requires. The KDA and KDB cannot, which is why the original Gepard, Type 87, GDF-001 and GDF-002 cannot fire AHEAD in baseline configuration, and why they require retrofit to the GDF-006 or GDF-007 standard. Türkiye took the KDC-02 gun under MKE licence, added an Aselsan-developed muzzle Programming Module Device (PMD) and fire-control integration, then produced the indigenous ATOM round to feed it. The licence delivered the gun and the calibre. The airburst capability is Turkish industrial intellectual property layered on top.

MKE Kırıkkale Ammunition Factory now produces the loaded ATOM round under the 35 mm Air Defence System Modernisation (HSSM) and Particle Ammunition Supply (PMT) contracts. Aselsan manufactures the fuze electronics, with a reported delivery of 100,000 fuze-electronics units. TÜBİTAK SAGE handles the airburst electronics design and qualification authority. A separate Fragmentation Anti-Drone Ammunition family entered Turkish Armed Forces service in November 2025 alongside TOLGA. The picture confirmed across multiple WDS 2026 briefings is a fourth NATO-adjacent 35 mm production hub running at scale, and one the alliance has not yet finished counting.

IP and export structure. Two distinct regimes apply. Conventional MKE 35 × 228 (HEI-T, TP, TP-T) sits on a historic Oerlikon-Contraves licence. The open record does not detail the third-country export provisions, though the standard pattern from that licence generation is national-forces supply with OEM consent for third-country sale. ATOM is different. It is Turkish IP under the Aselsan / MKE / TÜBİTAK SAGE consortium and falls under the Turkish export-control regime, not Rheinmetall's. Reported ATOM-system exports to date sit at the system level (KORKUT, TOLGA, GOKDENIZ packages to Qatar, Egypt, Saudi Arabia, and the Hungary HT Division MoU), not loose-round sales.

Source rating: Defence Turkey reporting on KDC-02 licence and ATOM production, B-2. KORKUT/TOLGA/GOKDENIZ gun designation as KDC-02, Wikipedia composite confirmed against Aselsan product literature, B-2. Aselsan production milestone (100,000 fuze-electronics units), B-2. ATOM operational equivalence to AHEAD, B-3 (see Section 8 for the technical maturity distinction).

Section 4
How the gun knows when to detonate, and why older systems can't

Programmable airburst in 35 mm × 228, AHEAD, ATOM, the new MKE Fragmentation Anti-Drone family, is hardware-gated, not software-gated. The system relies on three inductive coils positioned at the muzzle after the end of the rifling:

1. Coils 1 and 2 sit approximately 10 cm apart and measure each round's actual muzzle velocity to better than 0.5%. Round-to-round velocity variation is the dominant source of airburst placement error, so individual measurement is essential.
2. The Programming Module Device (PMD) computes the corrected time-of-flight to airburst using the fire control unit's predicted intercept point and the measured velocity.
3. Coil 3 imparts the corrected ejection time to the projectile fuze by electromagnetic induction as the round transits, no contact, no slow-down, full cyclic rate maintained.

If those coils are not present, the round leaves the barrel un-programmed and functions only on its backup Point-Detonating Self-Destruct (PD-SD) fuze, which negates the entire purpose of buying an airburst round in the first place.

The AHEAD-capable gun population, per Rheinmetall product literature, is four guns: the KDC, the KDG revolver, the MK35-1 (the electric-drive cannon inside the Oerlikon Revolver Gun Mk3 / Skynex generation), and the ATK (Northrop Grumman) Bushmaster III. That excludes the KDA (Gepard, Type 87), the KDB (GDF-001 and GDF-002), and every system built around those two guns in their baseline configuration. The Turkish KORKUT, TOLGA and GOKDENIZ all chamber the KDC-02 (the same gun family the Rheinmetall brochure lists) with an indigenous Aselsan PMD and fire-control loop.

Inside the AHEAD-eligible population, the further distinction is between mounts that ship with the muzzle programmer integrated and mounts that need a kit. The KDG revolver in Skyshield, MANTIS, Skyranger 35 and Millennium 35/1000 was designed for AHEAD from the outset. The MK35-1 in the Oerlikon Revolver Gun Mk3 (Skynex) inherits the same architecture with an electric drive that decouples reliability from gas pressure. The towed KDC mounts split into baseline (GDF-003 and GDF-005, with no AHEAD as standard) and the upgrade variants. GDF-006 is an AHEAD retrofit kit applied to legacy GDF-001, GDF-002 and GDF-003 mounts. GDF-007 is the AHEAD retrofit applied to GDF-005. GDF-009 is the 2015 IDEF-launched four-wheel-carriage version with integrated battery and AHEAD capability that "requires some modification of the ballistic computer". The retrofit path itself is routine within the Rheinmetall portfolio; older twin-gun systems are designed to receive the muzzle programmer kit. The Turkish KDC-02 with Aselsan PMD is the parallel solution to GDF-006, GDF-007 and GDF-009: same gun family, indigenous airburst integration, Turkish industrial supply chain.

Standards framework. The controlling NATO standard for the cannon-and-round combination is STANAG 4516 (Cannon (Greater Than 12.7 mm), Design Safety Requirements and Safety and Suitability for Service Evaluation of the Weapon/Munition Combination). Qualification under STANAG 4516 applies per gun-and-round configuration, not per round in isolation. Energetic-material qualification sits under STANAG 4170 and AOP-7 (Edition 2). AOP-7 §1.5 states that material qualification "does not imply Final (or Type) Qualification for use in a specific hardware application." Quality management of the manufacturing process sits under AQAP-2110. STANAG 4429, titled "35 mm by 228 Ammunition" and the older calibre-specific framework, was withdrawn around July 2013. No active calibre-dimension STANAG exists for 35 × 228 today.

The practical consequence: when a GDF-001 or GDF-002 mount is upgraded to GDF-006, or a Skyguard line to GDF-007, the gun-and-round combination changes and fresh STANAG 4516 S3 evaluation is required. HEI-T/SD and TP-T tend to grandfather across upgrades, because the AOP-7-qualified fill plus PD-SD fuze in an established all-up-round architecture is the most permissive case. KETF rounds require fresh qualification on each new gun configuration: fuze-electronics S3, ballistic-table re-derivation, PMD calibration. ATOM is qualified specifically with KORKUT, TOLGA and GOKDENIZ; Rheinmetall maintains separate PMD062 and PMD428 qualification dossiers across the KDG, MK35-1 and Bushmaster III population.

The practical effect is that a large slice of the legacy GDF towed inventory in NATO and partner forces, every GDF-001 and GDF-002 still in service, plus any GDF-003/005 that has not been upgraded to GDF-006/007, cannot fire AHEAD without a muzzle-collar retrofit and a fire-control integration that is more invasive than a software update. The same is true of every Flakpanzer Gepard in original KDA configuration, the Japanese Type 87, and the Chinese Norinco PG-99 / Type 90 clone.

Section 5
KORKUT (Aselsan): the mobile SPAAG

KORKUT is Aselsan's tracked Self-Propelled Anti-Aircraft Gun (SPAAG), built on an FNSS ACV-30 hull and armed with twin Oerlikon KDC-02 35 mm autocannons manufactured under licence by MKE. The system entered Turkish Land Forces Command (TLFC) service in 2016 and was reportedly engaged operationally in Libya in support of the Government of National Accord, providing the first combat data points on the platform's effectiveness against rotary-wing and unmanned threats.

In WOME engineering terms KORKUT is conventional. The twin-mount feeds from box-fed magazines. The on-vehicle radar is a search-and-track set in the X-band region of the spectrum. The fire control system feeds gun-laying commands to the turret with allowance for tracer burn-time observation and ATOM airburst programming via the muzzle-fitted Aselsan PMD. The cyclic rate sits in the standard KDC-family band of approximately 550 rounds per minute per barrel, giving a combined 1,100 rpm at the muzzle. The ready magazine load is sized for short bursts, not sustained area suppression. The defining design choice is mobility: the ACV-30 hull keeps the gun moving with armoured manoeuvre elements, where a Fixed Air Defence Position (FADP) cannot. For an alliance now investing heavily in countering Class 1 and 2 Unmanned Aerial Systems (UAS) and First-Person View (FPV) loitering munitions against manoeuvre forces, that mobility is the differentiator.

Operator base reported as Türkiye with at least one undisclosed export customer (assessment: low-to-medium confidence, C-3).

Section 6
TOLGA (MKE): the modular base-defence system

TOLGA is structurally different. MKE designed it from scratch as a Counter-Unmanned Aerial System (C-UAS) and base-defence weapon, not as an adaptation of a legacy SPAAG. The 35 mm channel is also different: TOLGA mounts MKE's indigenous 35 mm Revolver Gun (the five-round drum design first shown at SAHA EXPO 2024 and IDEF 2025), not the licensed KDC-02 carried by KORKUT and GOKDENIZ. Cyclic rate is adjustable from 1 to 1,500 rounds per minute, sized for the dense-engagement regime that drone swarms impose, and the maximum hard-mount recoil force stays within 68 kN. The reference architecture combines that 35 mm Revolver Gun with a co-mounted 20 mm cannon and a dual 12.7 mm machine-gun fit in a single multi-calibre fire unit. Supporting it: an Active Electronically Scanned Array (AESA) radar, an Electronic Warfare (EW) jamming suite, and an AI-assisted fire control loop that selects calibre and engagement geometry per target. The Turkish Armed Forces confirmed the system's performance after a series of live-fire engagements against unmanned aerial targets on 16 November 2025, reporting 100% engagement success.

The three-calibre layering is the doctrinal innovation. Against a Class 3 fixed-wing UAS or a cruise missile, TOLGA presents an ATOM airburst engagement at 2–4 km. Against a Class 2 quadcopter swarm at 800 m to 2 km, the 35 mm continues to engage with conventional HEI-T while the 20 mm assumes leakage targets. Against the close-in FPV and Group 1 UAS threat inside 1 km, the 12.7 mm becomes the primary effector, conserving 35 mm rounds whose unit economics make sustained engagement against cheap targets uneconomic. The AESA radar provides simultaneous track and engagement-quality data across the volume, and the EW suite gives the operator a soft-kill option before a round is fired.

The deployment options matter as much as the firepower. TOLGA is offered as a fixed Forward Operating Base (FOB) emplacement, a vehicle-mounted module on the 4×4 PARS family or equivalent, a naval mount, and a deck-mounted system for Uncrewed Ground Vehicles (UGV). Reported export contracts in the first quarter of 2026 cover Qatar (a joint-venture arrangement with MKE), Egypt, Saudi Arabia, and a Memorandum of Understanding with Hungary's HT Division (C-2: contract existence confirmed by multiple regional defence press; configuration and quantities not independently verified).

Net Explosive Quantity (NEQ) per ATOM round is not openly disclosed by MKE. An ISC working estimate based on reported munition type (KETF, 35 × 228, mixed fill of pressed RDX/HMX-based projectile fill plus pyrotechnic time-fuze train) places the per-round NEQ in the low tens of grams (data gap declared, C-4, not independently verified). The loaded round's Hazard Division and Compatibility Group for the baseline HEI-T configuration are HD 1.2 D, with airburst variants subject to additional IM characterisation under the national authority. Storage and movement come under Defence Safety Authority (DSA) 03.OME, which replaced the now-retired Joint Service Publication (JSP) 482. Precise magazine layout for the reference TOLGA fire unit has not been published in primary MKE technical data; the basic load aggregate is therefore an inference, not a measurement.

Section 7
Compatibility matrix: which systems can fire what

Before the system-by-system matrix, the gun-level position. The AHEAD-capable gun population, per Rheinmetall product literature, is four guns: KDC, KDG, MK35-1 (Mk35e — electric-drive cannon in the Oerlikon Revolver Gun Mk3 / Skynex generation), and the Northrop Grumman Bushmaster III.

Source: Rheinmetall AHEAD product brochure B038e0424 plus current Oerlikon Revolver Gun Mk3 product literature (D712e0524). Source rating: A-1. The MK35-1 inherits the KDG-family AHEAD architecture with an electric drive — Rheinmetall product data states the gun "delivers maximum combat effectiveness up to 3,000 m" and "the highest degree of fighting power is achieved in combination with the 35 mm KETF ammunition". The KDA and KDB are excluded by physical configuration: neither hosts the inductive muzzle programmer. Adding it is a routine retrofit within the Rheinmetall portfolio (a muzzle-collar plus fire-control integration), and is exactly the path taken in GDF-006 / GDF-007 — older twin-gun systems can be moved to AHEAD-capable status more readily than the article's earlier framing implied.

The Oerlikon GDF mounts themselves follow this hierarchy:

Source: Wikipedia composite cross-checked against Forecast International GDF Series profile and Army-Guide entries, B-2 for variant-by-variant gun assignment, A-2 for AHEAD-capability of GDF-006/007/009 (consistent across all open sources). The user’s framing, "only the latest Rheinmetall guns and the Turkish guns can fire AHEAD", is essentially correct: AHEAD-capable means KDG revolver, Bushmaster III, or KDC-with-PMD (in the form of GDF-006/007/009 or Turkish KORKUT/TOLGA/GOKDENIZ).

The system-level matrix below uses these gun-level facts. ✓ = compatible in current production configuration; ◐ = compatible only after modernisation or retrofit; × = not compatible.

Reading notes: The matrix shows gun-and-platform compatibility, not export availability, ATOM and the MKE Fragmentation Anti-Drone family are subject to Turkish export approvals. Bushmaster III is the only gun in the matrix that natively chambers APFSDS-T (anti-armour), because it is also an Infantry Fighting Vehicle (IFV) main gun. The Turkish KORKUT/TOLGA/GOKDENIZ marked ◐ in the AHEAD column are technically compatible (KDC-02 with PMD) but the AHEAD round itself is a Rheinmetall product; Turkish operators use ATOM, which is the Aselsan-MKE airburst round designed for the same gun and the same muzzle-programmer architecture. Source rating across the matrix: B-2 average; cells marked ◐ are C-3.

Section 8
AHEAD / KETF family and the Turkish ATOM equivalent

"AHEAD" is best understood as the original member of the broader Kinetic Energy Time-Fused (KETF) cartridge family in 35 mm × 228, not as a single round. Rheinmetall currently fields at least two distinct KETF rounds plus an un-programmed mode, each documented in its own product literature:

• AHEAD / KETF PMD062, the original AHEAD round. 152 tungsten cylinders (~3.3 g each), ~500 g total payload, projectile total mass ~750 g, muzzle velocity ~1,050 m/s, effective range ~4 km. Optimised for the broad aerial target set: fighter-sized aircraft, cruise missiles, rotary-wing, and rocket-artillery-mortar.
• ABM / KETF PMD428, the counter-UAS-optimised variant. Approximately 675 sub-projectiles per round (rather than 152), each smaller, sized to maximise lethal coverage against small fast-manoeuvring drones. Demonstrated against an 8-drone swarm in a 2021 Bundeswehr trial — most of the swarm neutralised within an 18-round burst, the majority destroyed in the first six rounds.
• Un-programmed KETF, the same physical round fired without muzzle programming, which functions as a frangible armour-piercing round against ground or surface targets. This is a configuration mode, not a separate cartridge.

The Turkish ATOM family under the Aselsan / MKE / TÜBİTAK SAGE consortium is the operational analogue of the AHEAD / KETF line. Two production variants are confirmed in open Aselsan literature:

• ATOM 35 ABM, the original Air Burst Munition. Base-fuzed, spin-stabilised, programmed inductively at the muzzle. Qualified for the GOKDENIZ naval CIWS and modernised towed gun systems.
• ATOM 35 IABM, Intense Airburst Munition. Tail-fuzed (a different fuze location from ATOM 35 ABM), with a denser sub-projectile pattern from a higher count of smaller pellets. Aselsan's product page positions IABM for IFV mounts and the GÖKER (KORKUT 110/35) configuration, with stated effectiveness up to 5 km against personnel and up to 2 km against mini and micro UAVs.

Both ATOM variants share the muzzle-programmer architecture used by AHEAD / KETF. The differences against the Rheinmetall family lie in documentation and qualification scope.

• Documentation maturity. Rheinmetall's PMD062 and PMD428 each have a published product brochure with stated sub-projectile counts, masses, payload geometries and the platforms against which they are qualified. ATOM's equivalent qualification dossier is not openly documented in the same way. Trade-press coverage stops at the operational claim level and does not reach the technical specification level. For procurement officers benchmarking quality, AHEAD and KETF remain the documented reference.
• Qualification scope. ATOM is qualified under STANAG 4516 with the specific KORKUT, TOLGA and GOKDENIZ configurations: KDC-02 plus Aselsan PMD plus the dedicated fire-control loop. Qualification does not transfer to a different gun configuration without fresh S3 evaluation. No third-country operator can field ATOM on a non-Turkish platform without standing up a fresh qualification dossier for the combined system first.

ATOM is a credible operational analogue. AHEAD and KETF are the documented benchmark.

Source ratings: AHEAD / KETF specifications from Rheinmetall product brochures B038e0424, D108e0721 (PMD062), D109e0721 (PMD428), A-1. PMD428 2021 Bundeswehr drone-swarm trial, A-2 (open trade-press confirmation). ATOM existence, production framework and platform compatibility from multiple WDS 2026 sources, B-2. ATOM detailed ballistics not in open MKE technical data, C-3 (operational analogue confirmed; technical specification dossier not openly published).

A separate Turkish development, the MKE Fragmentation Anti-Drone Ammunition family, entered Turkish Armed Forces service in November 2025 alongside TOLGA. It is designed specifically for the cheap-target, swarming-drone threat that makes ATOM uneconomic at unit cost, and operates on a fragmentation principle (likely pre-formed fragments dispersed by a fuze action that is either time-programmed or proximity-triggered, open-source detail is sparse and ISC has declared this a data gap).

Section 9
ISC commentary: the layering doctrine, not the gun

It is tempting to frame KORKUT and TOLGA as competitors. They are not. KORKUT is a manoeuvre-force SPAAG sized to move with mechanised brigades. TOLGA is a fixed and semi-fixed C-UAS and base-defence system sized to layer effects against a saturated low-altitude threat. Customers who signed in Q1 2026 are not choosing between them; they are buying both. They are doing so because the underlying 35 mm × 228 ammunition family is now sourced from three NATO production geographies, with a fourth Turkish hub running at production scale.

The Spanish-NAMMO arrangement is documented publicly only in the 2024 NAMMO Ammunition Handbook entry recording the 35 mm HEI-T/SD round as "supplied to Spanish MoD for 35 mm Oerlikon KDB gun", and is not accompanied by any open contract-announcement record. It was read in some quarters as a single-country anomaly. With Unterlüß open since August 2025, with MKE Kırıkkale producing ATOM and the Fragmentation Anti-Drone family for both Turkish operators and an expanding Q1 2026 export book, and with NAMMO Palencia now a credible second source across the alliance, the calibre has crossed from monopolistic risk into commodity supply. The platform-level competition is no longer about which gun can fire 35 × 228. It is about which fire control, which radar, which AI loop, which EW suite, and which calibre-layering doctrine the operator buys to wrap around it.

The Turkish architecture is the clearest current expression of that shift. It is also the reading NATO procurement is most likely to draw from a quiet 2026.

Section 10
Capacity, export rights and gun-specific qualification

The article needs to hold three separate constraints distinct. Conflating them gives a misleading reading of where alliance supply security actually sits.

The practical effect: a country that operates KORKUT cannot simply substitute Polish-manufactured MESKO FAPDS-T or Korean Poongsan HEI-T into a TOLGA fire unit without the right qualification dossier. Conversely, a country that operates the original Gepard 1A2 cannot draw on Turkish ATOM production for an airburst capability without three separate prerequisites: a muzzle-collar retrofit (gun configuration change), fresh STANAG 4516 S3 evaluation of the new combination, and Turkish export authorisation. Alliance supply security at the calibre level is real and improving. Supply security at the specific-platform level is narrower and more contractually constrained than the calibre framing suggests.

Standards framework summary. STANAG 4516 (Cannon >12.7 mm Design Safety and S3 evaluation of the weapon-munition combination) controls the gun-and-round combination. STANAG 4170 and AOP-7 (Edition 2) cover energetic-material qualification. AOP-7 §1.5 states that material qualification "does not imply Final (or Type) Qualification for use in a specific hardware application". AQAP-2110 covers the manufacturing quality management baseline. STANAG 4429, "35 mm by 228 Ammunition", was withdrawn around July 2013. No active calibre-dimension STANAG exists for 35 × 228 today, in contrast with 5.56 × 45 (STANAG 4172), 7.62 × 51 (STANAG 2310) or 30 × 173 (STANAG 4624). Cross-supplier interchangeability rests on the combination of: (i) STANAG 4516 weapon-munition combination qualification, (ii) AOP-7 and STANAG 4170 energetic-material qualification, (iii) the AQAP-2110 quality management baseline, and (iv) the specific OEM IP licence on any variant beyond conventional HEI-T, TP-T or FAPDS.