The following are known Action Replay Codes for Gunbird 2 on SEGA Dreamcast (Dreamcast). These codes were also known as GameShark Codes and in most cases will work on both devices.

Device Compatibility: Action Replay & GameShark

(M1)
9C5D88F8

(M2)
245EECA9

Infinite Specials
EE787862
00000002