An improvised firearm reportedly of a type used to murder British MP Jo Cox yesterday. The suspected shooter allegedly owned a copy of US Army ‘TM-31-210 ‘Improvised Munitions Handbook’ published in 1969 which contains detailed instruction on how to construct various simple homemade guns including the pistol pictured. The pistol is assembled from a 1/4″ pipe coupled with a plug fitted with a nail to act as a firing pin. It is fired by pulling back and releasing a metal strap which is powdered by multiple elastic bands wrapped in place. Reportedly the designs were extensively tested in trails and deemed safe enough to publish for official use.