|Birch Gun Mk II|
|Place of origin||United Kingdom|
|Weight||12,100 kg (26,500 lb)|
|Armour||6 mm (0.24 inch) Steel|
|1 x 75 mm (2.95 inch) Gun|
|Engine||1 x Armstrong Siddeley 8 cylinder petrol
90 hp (67 kW)
|192 km (119 miles)|
The Birch Gun was the world's first really practical self-propelled artillery gun, built at the Royal Arsenal, Woolwich in 1925. The gun was never highly regarded by the British High Command, purely for prejudicial beliefs and political pressure rather than any real lack of ability. Named after General Sir Noel Birch, who was Master General of Ordnance at the time, the Birch gun had real potential. It was built upon a Vickers medium tank chassis and mated originally with the 18 pdr (83.8 mm) then with a 75 mm field gun. The project was abandoned in 1928 after political pressure killed off any plans to complete the third version of this weapon.
The armament for the original Birch Gun consisted of a Ordnance QF 18 pounder field gun (3.3 inch, 84 mm). This was changed to the 75 mm gun on the Birch gun Mk II and from then on was able to be fired either at ground targets or in the air-defence role, being given a much higher rate of elevation to be fired at enemy aircraft.
The Armstrong Siddeley engine was modestly powerful being only 8 cylinders it could manage 90 hp for a mild 45 km/h top-speed however, for its time (late 1920s) it was quite fast.
The Birch gun was tested as part of the Experimental Mechanised Force in the 1920s. The Force undertook various experiments in mechanized warfare combining tanks and infantry with their own transport.
The composition of the force was: