In The Great Escapist, Crowley reveals his new invention, an Angel-Killing Gun which he produced by melting down angel blades. He demonstrated its effectiveness by killing Esper and wounding Ion. He also shot Castiel with a bullet in order to retrieve the Angel Tablet hidden inside his stomach.
Castiel uses that same bullet he was shot with to kill Ion by forcing it into Ion's eye.
In All Along the Watchtower Castiel, Sam, and Dean discover an alternate universe in which humans hunt angels and are equipped with guns loaded with angel-killing bullets. During his arrival in that world, Castiel was saved from a Tempter Demon by Bobby Singer with a shotgun loaded with angel-killing rounds.
In Good Intentions, when Zachariah and his angels attack Bobby Singer's colony, the defenders kill many of the angels with weapons loaded with angel-killing bullets. Bobby arms Mary Winchester with a gun loaded with the bullets as well, but she is disarmed by Zachariah before she can use the gun on him.
In Bring 'em Back Alive, after an ambush by a bounty hunter in Apocalypse World, Dean and Arthur Ketch find the man's guns loaded with angel-killing bullets. Arthur was amazed by the creativity and effectiveness of the bullets. The two men later use the weapons to kill several angels while rescuing Charlie Bradbury from a prison camp. As Dean departs Apocalypse World, Charlie and Arthur use guns loaded with the bullets to battle several attacking angels.
In Exodus, members of the resistance are armed with guns loaded with the bullets. Before being captured by several angels, Arthur and Charlie use an assault rifle and a shotgun loaded with the rounds respectively when confronting the angels.
- Bobby Singer
- Dean Winchester
- Members of Bobby Singer's colony
- Bounty Hunter
- Arthur Ketch
- Charlie Bradbury