Resident Evil 5 Infinite Ammo

- Completing all of a weapon's upgrades unlocks Infinite Ammo on the second playthrough
- Feature can be enabled after completion of the game from the Bonus Features menu
- Completing all upgrades can take considerable time, depending on the weapon
- Beat the game in under five hours to unlock Unlimited Rocket Launcher

While playing Resident Evil 5, the player has the opportunity to perform numerous upgrades on the various weapons they collect. Costing in-game money, these upgrades give each weapon perks like a higher ammo capacity or longer range. Once all the upgrades on a weapon are complete, that weapon will have infinite ammunition on the player's second playthrough of the game.
As in Resident Evil 4, a complete playthrough is required to unlock the Bonus Features menu, increase the statistics cap of your weapons, as well as to unlock the permission to play with infinite weapons.IGN: Resident Evil 5 Artificial Intelligence
About Resident Evil 5

Resident Evil 5, from developer Capcom, picks up the story from where Resident Evil 4 left off. IGN: Resident Evil 5 Coming (March 4, 2005)
In this adventure, the player takes control of Chris Redfield for the first time since Resident Evil: Code Veronica. Chris, a member of the Bioterrorism Security Assessment Alliance (BSAA), is sent to a remote African village to investigate an incident which took place there. Once arriving, he soon realizes that things aren't as he expected and is thrown into a fight for survival. GameSpot: Takeuchi talks Resident Evil 5 (August 2, 2005)
Helping Chris on his quest is Sheva Alomar, also of BSAA, who assists the player in collecting items, fighting off enemies, and supplying health when needed. She is also the character the second player uses when playing in Co-op mode.