R. Meyer J. Köhler A. Homburg Explosives

Caseless Ammunition
Caseless Ammunition
Hülsenlose Munition; munition sans douille
The requirement to improve portable firearms resulted in a reduction
of the caliber (dimension 4–5 mm); and to reduce the ammunition
weight led to the caseless ammunition project. Moreover, in the event
of a crisis the problem of a worldwide shortage of nonferrous metals
for cartridge cases will arise.
For a considerable time the caseless ammunition consisted of a
compressed NC propellant body into which the bullet was inserted.
However, this propellant tends to self-ignition even at relatively low
temperatures (ca. 170 °C). Thus a “cook-off” may result, i.e. a premature
ignition in a hot cartridge chamber which may occur with all
automatic guns. In addition, with caseless ammunition the heat which
is otherwise transfered to the cartridge case remains in the cartridge
chamber. Therefore, in order to avoid the “cook-off”; HITPs (High
Ignition Temperature Propellant) have been developed worldwide.
DNAG used such a propellant for the first time with caseless cartridges
for a newly developed gun (G 11) from Messrs. Heckler &
Koch. The essential innovations with regard to previous developments
are the use of a high-temperature-resistant, non-crystalline explosive
as binding material, a special granular shape for the main energy
component and the possibility to adjust the interior ballistics by porosity
and stability of the propellant body. Further new developments are
the combustible primer and the booster.
Fig. 8. Sectional view of the caseless cartridge body (Calibre 4.73 mm) for the
G 11 weapon system.
Casting of Explosives
Giessen von Sprengladungen; coulée de charge de projectiles
Since the brisance of an explosive largely depends on its loading
density, the highest possible loading densities are employed, in particular
for military explosives. This density is attained by casting or
pressing. The pressing operation requires a technical device. A cast
charge is easier to fit into shells, mines and bombs, which have rather
complex-shaped internal profiles.
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