Intertechnik has developed a semi-automatic loader and an automatic primer feed for installation on the US-designed United Defense 155 mm M109 series of self-propelled howitzers.

This can be installed on new-build vehicles or fitted on to older vehicles as part of an upgrade.

Both systems have been developed by Intertechnik to increase the rate of fire of the weapon and to minimise the workload of the turret crew.

Using the semi-automatic loader and the automatic primer feed, a burst rate of fire of 3 rounds in 11 seconds and a sustained rate of fire of 6 rounds in 29 seconds has been achieved in test firings.

The semi-automatic rammer enables 155 mm projectiles up to 1m in length to be loaded and rammed much faster than the current manual method, so enabling a higher rate of fire to be achieved.

Features of the system include microprocessor control and integral autotest for both automatic and manual operation to reduce demands on the turret crew.

All the motion switches are hydraulically controlled and monitored via position switches. The energy required can be obtained from the existing onboard DC/hydraulic unit.

The system consists of the following key parts:

(1) Weapon-mounted loader unit

(2) Electronic control plus operator interface

(3) Hydraulic manifold

(4) Installation kit

The automatic primer feed operates on the principle of a drum-type revolver carrying 10 primers per loading ring. The primers are aligned with the firing mechanism upon closing of the breech.

Every 10 seconds, the loading ring has to be changed to a new one with a further 10 primers. Key features include easy operation, minor breech modification for installation and remote firing trigger on the turret roof.

In production. As far as is known this system is not used by the Austrian Army.