5. The Hanes Grenade
A serious error in grenade-making was the horrifyingly-easy way they could be set off unintentionally.
The Hanes grenade, also nicknamed “The Excelsior,” was designed in the early 1860s, initially for the Union Army. Formed with hollow metal spheres filled with explosives, these grenades also had 10-14 metal protrusions that were then covered with percussion caps. If the grenade came in contact with a hard surface, the percussion cap would detonate and blow up the entire weapon.
As a result of being easy to detonate, however, they were never officially adopted or used in combat. Another model named the Ketchum grenade was more equipped for battle, and they saw combat in both Petersburg and Vicksburg.