.303 in Mk IV cordite dum-dum round

'Dum dum' bullets were designed to expand on impact and cause larger wounds than standard bullets. Outlawed as too cruel for 'civilized' Europeans, they were used in colonial wars against 'savages' when troops needed a bullet with greater stopping power. This round was made by the Birmingham Munitions Company. Its success at stopping charging tribesmen led other soldiers to improvise by filing the tips off standard bullets.