7.92mm BESA
Having adopted a much modified version of the Czech ZB 26 as the Bren gun in 1934, trials were held in 1936/37 with the intention of adopting a .303 version of the ZB53 medium machine gun as a weapon for armoured vehicles. However, the likelihood of a war with Germany being imminent it was decided to adopt the ZB53 in its original calibre of 7.92x57mm, since it would be unwise to embark on an extended development program in the little time available.
One of the attractions of the ZB53 was its alleged ability to handle any make of 7.92mm ammunition, and although trials with Czech ammunition had gone well that made by Kynoch had resulted in stoppages and separated case. This was found to be due to the Kynoch cases being over hardened and so Kynoch reduced the hardness until eventually in August 1937 produced a satisfactory batch of 10,000 rounds.
The Kynoch rounds used in the trials were either headstamped "K.37 7.9" or "KYNOCH 7.9 of 8mm".
The Czech rounds were headstamped "Z XI 1936". The illustrated case was found on the RSAF Enfield ranges in the early 1980s and is a survivor from those trials.
In addition to the formally approved ammunition for the 7.92mm BESA, there was special ammunition made in the late WW2 period for use with the experimental SLEM rifle. This will be covered separately when experimental ammunition is eventually added to the site.