BioShock

This achievement will unlock when you upgrade a second weapon fully. Each weapon has two distinct parts that you can upgrade, so that means the earliest you can get this achievement is at the game's fourth Power to the People station, which is in Fort Frolic.

1. Neptune's Bounty - room after defeating Peach Wilkins
2. Arcadia - one of the rooms right before the Farmer's Market
3. Farmer's Market - bottom floor of the Winery
4. Fort Frolic - Le Marquis d'Epoque (the southwest corner of your map)