Chesty Puller's Bullet Shells

Origin
Lewis Burwell "Chesty" Puller (June 26, 1898 – October 11, 1971) was a United States Marine Corps lieutenant general who fought guerrillas in Haiti and Nicaragua, and later fought in World War II and the Korean War. He commanded American troops while fighting for control of Guadalcanal and later helped retrieve allied South Korean land during the Battle of Incheon. For these collective actions, he is the only person to have received six of the nation's second-highest military awards for valor, five Navy Crosses and the Distinguished Service Cross.

Effects
Tapping two bullets together sends out an omnidirectional shock wave that can disable anything within 100 yards. Trying to move or operate them will only result in further damage. People that are affected will be unable to maintain their balance, suffer from loss of coordination, nausea, vertigo or have difficulty supporting their own weight.