Go to the Settings menu and enter the following cheat in the Cheats menu: DOWN, UP, DOWN, YELLOW. Doc's ammo reserve limits increase to 999 (instead of, say, 160 for guns or 4 for the Healing Tool) and then it gives you maximum ammo in all weapons. However, the amount is NOT infinite. You could always just put the code in again when you run out. The message displayed after the code is input reads "All Ammo Given!"

Submitted by roleModel23

Submitted/Verified by PyroFalkon