"Birch Guns" Topic

The British built a small number of experimental self propelled guns. These were fully tracked weapons based on existing chassis and mounting the current 18 pdr field gun. The carriage allowed full traverse as well as high elevation. This gave the weapon a dual function as both a field artillery weapon and an anti aircraft one. A latter version put a turret like structure over the gun.
This may have been too ambitious in terms of asking the 18 pdr to do a task for which it was unsuited. Also tank enthusiasts within the British Army were concerned that if an artillery vehicle had such a big gun what was the role of the tank these were supposed to support?

All things considered though the Birch Gun was in many ways better than any SPG put into service by the British Army during WW2. It had full traverse and allowed the gun to reach its full ballistic range because it had elevation over 45 degrees. To me it is always sad that the Royal Artillery wasn't able to field these in large numbers, or a successor vehicle with a 25 pdr.

I do have a couple of questions. Could the 25 pdr have been fitted on this chassis? Could the 3 inch 20 cwt anti aircraft gun been mounted as an alternative? Either of these would have been really useful both in their respective primary roles of field artillery or anti aircraft fire but also as anti tank vehicles. The increased mobility and armor protection would have made these weapons much more survivable and agile. Both these guns were more than capable of killing any German tank up to Panzer IVs.

It seems like yet another place were the British had a lead over everyone else in the 1920s and 1930s and just squandered it.

Let's don't forget that the Birch Gun was an automotive nightmare and, in the field, would have been highly unreliable.

Here's the Wiki article on it. en.wikipedia.org/wiki/Birch_gun

Even though the tank chassis was "an automotive nightmare" as Ross said, the concept had great validity, which was, of course, proved during and after WW2.

Jim

They did make an experimental SP 3 inch AA on a tracked chassis, I don't remember if it used the same chassis as the Birch, the article I read was more about British AA guns rather than tracked guns.

Vickers photos of the three types of Birch Guns (without shield; with shield; and barbette) can be seen on the Interwar Tank Development blog here:

link

David Fletcher gives a good description of the mechanical issues in Moving the Guns. He questions the source of these troubles as the chassis was closely based on the well regarded Dragon series of machines. Also to be mentioned is only five of these were made. Often more than that number of prototypes is needed to move a design into full series production and operational service, especially since the entire field of AFV design and engineering was only around a decade old. In many ways the British Army didn't get a machine of a similar concept until the post WW2 Abbott.