The LIW 20 mm GA1 automatic cannon is an improved version of the German 20 mm MG 151 20 mm automatic cannon and is suitable for installation on aircraft, helicopters, light vehicles and armoured fighting vehicles including infantry fighting vehicles.

As far as is known, the GA1 has not been installed in any standard production armoured fighting vehicles in operational service with the South African National Army. It is operational in helicopters used by the South African Air Force.

The 20 mm GA1 automatic cannon has a very low recoil force which, according to LIW, together with its external geometry, makes it very suitable for installation on hand-held or automatic mountings. It can easily be adapted for left or right-hand feed and is recoil operated, firing from the open bolt position.

The low-recoil advantage stems from the relatively light cartridge. The original German 20 x 82 mm Mauser cartridge carried a 115 g projectile with a muzzle velocity of 705 m/s. The new cartridge, produced by Pretoria Metal Pressings, is referred to as a 20 x 83.5 mm; the case has had the shoulder shortened and the neck lengthened to give better support to the projectile.

The overall length of the complete round remains the same at 146.5 mm.

The 20 x 83.5 mm round has a 110 g projectile with a muzzle velocity of 720 m/s. HEI, HEI-T, SAPHEI, TP and TP-T rounds are available for this weapon.

case has had the shoulder shortened and the neck lengthened to give better support to the projectile.

The overall length of the complete round remains the same at 146.5 mm.

The 20 x 83.5 mm round has a 110 g projectile with a muzzle velocity of 720 m/s. HEI, HEI-T, SAPHEI, TP and TP-T rounds are available for this weapon.

Vektor GVM vehicle mount, a dual version with two GA1

cannons is also available

Vektor SMM 10 single marine mount

Vektor GMM 20 dual marine mount.

Vektor is the trade name for small arms and medium-calibre weapons produced by the LIW division of Denel.

By adding two components, a feed plate and a barrel jacket and changing the barrel and bolt assembly, the 20 mm GA1 cannon is converted to a 12.7 mm machine gun.

Status

Production as required. In service with the South African National Defence Forces.