Mortar mobility enhanced by the new M3 weapon system

The Finnish Defence Forces will procure up to more than hundred vehicle-fitted and -mounted mortar systems from Patria Land. Modular and mobile, the new 120mm mortar M3 weapon system will improve force mobility, protection, and fire delivery capability over a wide area.

The Army has developed in co-operation with the Finnish Defence Forces’ Logistics Command and Patria Land a new M3 mortar system (M3 denotes Modular Mobile Mortar). The Army employs the pre-series of M3 in training use since the start of 2026. 

The procurement contract with its options allows for procurement of hundreds of systems. The total value of the procurement to be now executed will be EUR 49,9 million excluding VAT.

– The new M3 system improves our force mobility, protection, and capability for fire delivery. The Army’s area of responsibility is wide, and a number of systems will be necessary. Now at the first phase, up to more than hundred systems will be procured, and the agreement with its options allows for the procurement of altogether hundreds of systems to all areas ranging from Hanko to northernmost Lapland, says Inspector of Infantry, Colonel Ari Mure from the Army Command.

Conscript training is already underway using the pre-series mortars, and the first weapon systems of the new series will be fielded this autumn.

Significant capability for infantry indirect fire support

Heavy mortars are employed to support the maneuvering forces. A part of the Army combined joint fires, the mortar systems have an increasingly significant role as an organic indirect fire unit. It enables rapid delivery of effects to counter an enemy also when, for instance, drones are non-utilisable.

The new heavy mortar system 120mm M3 is a significant capability for infantry indirect fire support. The mortar system is ready for fire direction without specific preparations independent of soil conditions, and its rate of fire equals that of a towed mortar.

The weapon system is fitted and mounted onto a vehicle by standard container twist locks, and the call for fire will be executed directly onboard. The system utilises the already existing mortar barrel and battle management system that have been integrated to the module’s ammunition magazine, recoil mechanism and inertial navigation system. The module allows fires onboard all standard container twist lock -fitted vehicles. In case of vehicle malfunction, the module can be transferred onto another vehicle to continue mission task execution.

– The system enables starting indirect fire support nearly instantaneously after the vehicle comes to a halt. Operating as a firing unit, the mortar company is capable of accurately firing 144 heavy mortar rounds at the target per minute from dispersed firing positions, and egressing to cover from counter measures while the projectiles are still in flight, explains Colonel Mure.  

Finnish-made with secured supply of spare parts, the system is easy to use and offers a very const-efficient solution thanks to how it utilises the already existing and field-proven components such as mortar barrels, battle management systems, and vehicles, as well as the previously signed framework agreement for inertial navigation system equipment.

Movement and maneuver are decisive, and modularity allows for multi-functionality

The development of mortar mobility is threat-driven. An unfortified mortar has no protection to counter air-to-ground threats, and it remains easily detectable when executing a call for fire. Modern weapon locating radars are almost immediately able to track and calculate the start point for a trajectory of a mortar projectile, and start counter measures to engage the firing weapon. A firing position is also vulnerable to aerial detection by satellites or drones even before the firing position is firing. Furthermore, significant range alone does not provide protection for the firing unit.

An efficient technique for threat-reduction is to execute a call for fire rapidly at a hasty firing position dispersed, and to egress for cover immediately after mission completion. Good tactical movement and maneuver will also compensate for projectile ranges. A vehicle-fitted and -mounted mortar system allows for executing the call for fire closer to the target, and relocating after mission completion. The add-on ballistic protection of the weapon module and armoured vehicle provide cover from bullets and shrapnel if movement and maneuver fail to suffice. The mortar barrel and battle management system can be easily detached from the module by the crew, and then use the heavy mortar conventionally from a heavily fortified firing position as applicable. In order to reduce close proximity distances and operating costs in training use, the barrel of the heavy M3 mortar system can be replaced by a light mortar barrel to fire light mortar rounds in live fire exercises.