Updated: Feb 13
Somchem is the only local commercial propellant manufacturer, and also supplies propellants dedicated to the only commercial ammunition manufacturer PMP who supplies the world's militaries with particularly sniper ammunition.
Somchem started as a private concern many years ago and was bought out by military arms (including anti-tank vehicles and the 60 km range G5 and G6 155mm artillery) manufacturer DENEL.
A number of years ago Rheinmetal of Germany saw the quality propellants for artillery and small arms coming out under the Somchem name and bought a 51% majority share in Somchem-Denel propellants.
One often reads (and that is my personal experience) that the average burn rate between different batches of US propellants of the same name is in the order of 10% and that reloaders must always take that into account when deciding on start loads with a new batch of propellant. It is a historic fact that should Somchem have a larger than 2% velocity discrepancy between loads that local reloaders immediately are on Somchem's back demanding an explanation and withdrawal of that batch.
Local shooters are terribly critical of local arms and ammunition components manufacturers: we see firearms patriotism as a manufacturer displaying patriotism by supplying the best quality in the world - and we do not buy South African products if the quality is poor. This embedded culture has been the reason for consistent quality in all locally designed and built firearms like Musgrave, Lyttleton Engineering, Vektor, Sabi Rifles and the many custom rifle builders. The ammunition components manufacturers and PMP commercial ammunition simply have to be patriotic too to be supported.
By law Somchem is required to openly publish all the following information regarding every batch of propellant:
The velocity per load discrepancy relevant to the particular reference load (Somchem uses same rate Vihtavouri propellants as reference for every single propellant it manufactures).
Heat of the explosion.
Ratio of Specific Heats.
Co-volume per mass.
Propellant density (weight per volume).
As an example, the latest batch of S365 (a propellant dedicated to the 30-06) has only a maximimum 0.70% velocity deviation from the past five batches relative to the relevant Vihtavouri propellant used as reference.
Because of their higher surface friction coefficient Somchem also tests actual pressures vs. velocity attained with Barnes bullets. Local reloaders have come to have great trust in the start and maximum velocities presented by Somchem regarding their accuracy and relevancy to Maximum Average Pressures according to CIP standards to which South Africa subscribes.
All the internal ballistic information supplied in their information booklet is based on high-speed video and data capture of thousands of hunting rifle tests. They have no need to inflate velocity claims for their propellants and it will also be a legal transgression in terms of their obligation to publish their results in terms of the Vihtavouri referrence propellants. The maximum velocities shown in their tables are true safe representations at safe Maximum Average Pressure for that load and even foreign shooters will be wise to refer to the Somchem velocity tables as true indications of MAPs per muzzle velocity, even using other propellants.
There is presently no formal export of Somchem propellants to the USA mainly because of lobbying against it within the USA industry.
Somchem laboratories do, for a very low fee, any kind of mechanical and accuracy test for anybody on his target or hunting rifle. In about 70% of the enquiries regarding inaccurate rifles their response is: "You have an accurate rifle there, sir. We suggest you make some arrangements for breathing and let-off training with an expert target shooter...".