Reiatsu gun

A reiatsu gun refers to a category of weaponry developed as an experimental advancement from the zanpakutō. They were developed roughly 150 years before the main Bleach storyline. However, further research on the firearms indicated that the destructive blasts of reiatsu that were projected from the weapons destroyed spiritual targets outright, which prevented a shinigami from being able to purify a hollow to maintain the balance between the human and spiritual realms. Because of this discovery, reiatsu guns fell into disuse and became a rare find.