Dum-dum is the colloquial name for several types of modified ammunition for firearms. A Hollow point bullet is sometimes referred to as such. Normal jacketed ammunition that has had notches carved across the top is also called by this term. The effect of the latter is for the jacket to fragment upon impact into four chunks, along the cross indentation. This creates a shotgun type wound, with multiple exit points, and greater blood loss and trauma. However, the downside to altering a bullet in this fashion makes it less aerodynamic, and thus less accurate at longer ranges.
Originally, dum-dum referred to a new type of ammunition produced at the Dum-dum arsenal in British India in the early 1890s. Soon after the introduction of smokeless powder to firearms, full metal jacket bullets were introduced to reduce stripping by the new, higher velocities. However it was soon noticed that such rounds were less effective at wounding or killing an enemy than older lead bullets. Within the British Indian Army, the Dum-dum arsenal produced its now infamous solution; elsewhere the Army tried the Mark IV (1897) and Mark V (1899) hollow point rounds.
Dum-dum rounds were outlawed following the Hague Convention of 1899. However, some soldiers would occasionally try to modify a full metal jacket round into a Dum-dum by filing the gilding metal off the tip. Thus, Dum-dum came to mean a jacketed bullet illicitly or illegally modified to expand.
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Dum Dum can also be taken as:
* Dum Dum Pop, a ball-shaped candy on a stick(lollipop). * Dum Dums (band) a Guitar-pop band.