Robuta

https://www.bocn.co.uk/threads/1931-experimental-vickers-squeeze-bore-gun.70147/ 1931 experimental Vickers squeeze bore gun | British Ordnance Collectors Network Just arrived at the North East Aircraft Museum (NEAM) in Sunderland. It is apparently unique. Can anyone shed any light on it? squeeze boreexperimentalvickersgunbritish