15mm BESA

In the period immediately before WW2 a number of Czechoslovak designed weapons were adopted by Britain, either in redesigned form like the Bren gun or in their original form like the 7.92mm ZB53 and ZB60 (BESA).

The 15mm ZB60 was essentially an enlarged version of the ZB53, scaled up to use the 15mm cartridge. It was a large, heavy weapon weighing over 125lbs and over two metres long. A number of guns were tested in Britain in 1938 and a licence secured for manufacture by BSA. Production began in 1939 and the 15mm BESA was used to arm mainly armoured cars and light tanks as a replacement for the obsolescent .5 Vickers.

The 15mm BESA had a relatively short life, being largely withdrawn by 1944. The main types of service ammunition were armour piercing and armour piercing tracer although ball, tracer, drill and dummy were also made. A practice round was developed but never finally adopted or issued.

The ammunition was made by Kynoch and Greenwood & Batley. The armour piercing characteristics of the wepon were never fully satisfactory which was probably the main reason for its short life. 

The bullet for the 15mm BESA was unusual in that the envelopes was drawn in such a way as to provide two thin driving bands to grip the rifling. Some experimental solid steel armour piercing projectiles had normal copper driving bands.

Air Service

In January 1941 consideration was given to using the 15mm BESA (and the 7.92mm version) to augment aircraft armament in the event that enemy bombing action disrupted supply of the 20mm Hispano and .303 inch Browning guns. Some trials were carried out using weapons with the barrel shortened by 12 inches but by March 1941 the Ordnance Board stated that no further action was required regarding using the 15mm BESA for Air Service.