Saint Petersburg Declaration of 1868
The Saint Petersburg Declaration of 1868 is an international treaty that outlawed the use of exploding bullets by the 17 signatory states. The signatories reasoned that that bullets that either blew up or caught fire upon hitting a target were too lethal, making the practice uncivilized and barbaric.
Source: Wikipedia — Saint Petersburg Declaration of 1868 (CC BY-SA 4.0)