A buddy and me were playing some Legendary Co-Op on Oni: Sword Base and we found a data pad under the stairs near the end. He crouched and meleed while pressing RB to open it, and his gun fired into the ground. He let go of the buttons, and it continued to fire until he backed out.
I tried it with my DMR and it didn't do anything, so I tried with the Plasma Pistol and it charged it, but when I backed out it didn't fire. Kinda odd, and totally useless, but I felt like posting it.