The Biwarip machine carbine was a prototype British submachine gun.
The Biwarip was designed in the late 1930s, and submitted to the British Small Arms Committee for testing in August 1938. It was a very handy weapon, and a modern one at that. However, it was too light to sustain any sort of accurate fire, and was rejected with no recommendations for improvement.
The Biwarip was a simple blowback-operated submachine gun; it had no sights or stock and was designed to be fired one-handed. It featured perforated barrel housing and, as was standard of many submachine gun designs of the time, the magazine fed into the left side of the receiver.