During the South African involvement in Angola during the mid-1970's, it was found that the artillery pieces employed by the artillery arm were outranged by the opposing Soviet weapons. With the United Nations arms embargo in place, alternatives had to be sought. Contact with Dr Gerald Bull of the now defunct Space Research Corporation of Canada was established and when this Corporation folded, the technology was transferred to South Africa. Sadly, Dr Bull, described as a maverick American artillery genius, was assasinated in Brussels in 1990.

1. ORIGINS:

The technology consisted largely of a family of streamlined long range 155mm projectiles, now known as Extended Range Full Bore (ERFB). These projectiles were fired from a slender barelled gunhowitzer. When a base-bleed (BB) system is added to the projectile's tail, ranges over 40km can be achieved. This BB system burns once the projectile is fired and the resultant gases prevent drag - inducing tail eddies to occur and thus to reduce the range. The same principal applies to a golf ball, this being the reason a golf ball does not have a smooth skin but one with indentations.

In the early 1980's, the existance of the G5 towed artillery piece was revealed to the world and surprise was expressed that such an advanced system could be developed locally. The G6 was revealed in the mid 1980's. The G6 and G5 are build by LIW, a division of DENEL in South Africa.

2. DESCRIPTION

2.1 MAKING THE BARREL

The G5-G6 family of weapons is probably the most accurate and longest-ranged in its category. This is due to the almost 7m long barrel, the most important part of any artillery piece. Because of the tremendous stresses that these barrels are subjected to, a special steel is used to prepare the barrel. This process is called Electro Slag Refining. Steel so refined is free of inclusions and is superior to steel melted in air.

To make the barrel, a solid piece of ESR steel is forged in a process untill stretched about 9 meters, with a slight taper at one end. Test pieces are cut from the ends to undergo quality control.  Each barrel is also ultra-sonically tested for flaws.

A rough hole is first drilled down the centre of the barrel and is then enlarged in subsequent drillings. Hydraulic pressures are applied to the barrel to see if any distortion takes place. A press is used to straighten the barrel if it was bent in the above tests. Alignment and straightening takes place 8 times during the manufacturing process. Extreme care is taken during the final drilling and also during the cutting of the rifling into the barrel.

This gives a 45-calibre barrel fitted with a fume extractor and a single baffle muzzle brake, It has an interrupted thread breech mechanism and a pneumatically operated hammer to ram projectiles at all angles of elevation. Bagged charges are loaded by hand.