The UK Ministry of Defence (MoD) has stated that the British Army’s new Ajax armoured fighting vehicles (AFV) will not operate airburst ammunition from the 40mm main gun.
Developed by CTA International, the 40mm main gun fires a type of munition known as Cased Telescoped Ammunition intended to offer advantages over more conventional designs, in being more compact and providing increased reliability.
According to the MoD, the CTA International weapon is compatible with a range of ammunition types: Armour Piercing Fin Stabilised Discarding Sabot-Tracer (APFSDS-T); Kinetic Energy Airburst (KE-AB); General Purpose Round – Airburst – Tracer (GPR-AB-T); General Purpose Round – Point Detonating – Tracer (GPR-PD-T); General Purpose Round – Kinetic Energy – Tracer (GPR-KE-T); Target Practice – Tracer (TP-T); and Target Practice Reduced Range – Tracer (TPRR-T).
However, the UK Defence Procurement Minister Maria Eagle confirmed on 4 September that of the seven ammunition types, “only the APFSDS-T, GPR-PD-T, and TP-T have been procured for use on Ajax”.
According to CTA International, the KE-AB munition delivers a payload of tungsten pellets with a directional terminal effect, considered to be “particularly effective against all aerial threats”, as well as ground applications such as infantry or blinding vehicle optics or antenna.
| KE-AB characteristics | |
| Dimensions | 65 x 255mm |
| Ammunition mass | 3000g |
| Projectile mass | 1400g |
| Muzzle velocity | 900m/s |
| Dispersion | < 0.5 mrad |
| Effective range | 3500m |
The CTA 40mm main gun is able to reach an elevated firing angle of 85°, ideal for combating drones.
Ukraine war shows drone impact
The lack of an airburst munition for Ajax is notable given the proliferation of combat drones in the Ukraine-Russia war, where armoured vehicles have proven to be particularly vulnerable to attack from first-person drones and loitering munitions.
Such has been the impact of drone use in Ukraine, the British Army is exploring the benefits of so-called ‘cope cages’ fitted to armoured vehicles, effectively applique slat armour that serves to detonate incoming charges prematurely.
Earlier this week, the UK MoD confirmed its armoured cavalry programme will deliver a further 55 Ajax-series armoured vehicles between July 2025 and December 2025, for a total of 128 units delivered over the course of the year, according to new official figures.
Of 589 Ajax-series armoured vehicles, across six variants, being built for the British Army, 245 will be equipped with the turreted 40mm main gun.
