This little guide will help you solve the puzzles to get the weapons attachments you'll need to upgrade Carlos' arsenal in Resident Evil 3.
CQBR Assault Rifle
Carlos's main weapon will be the only one with attachments. There are three in total, and we suggest taking the time to collect them all.
Scope
Adds a sight for more accurate shots. This accessory will have the same effect as the sight for Jill's handgun.
When Brad Vickers arrives in front of the police station, he will appear as a zombie. Shoot him, you will get his S.T.A.R.S. card from his body. This card will allow you to open a few safes inside the police station. The briefcase containing the scope is in the west office on level 1F, at the end of the aligned desks.
Tactical Grip
Greatly reduces recoil for better stability when shooting.
To get the tactical grip, you'll have to wait until you're in the hospital. Go to level 2F and find a broken window with yellow ribbons on it. It'll allow you to go down into the yard on level 1F. The tactical grip is located near the hedges in a flowerpot.
High Capacity Magazine
Increases capacity to 64 rounds.
It's the second attachment to get in the hospital. The high capacity magazine is in one of the few safes in the game, the one at the nurses' station in 2F.
Don't waste your time looking for the combination here, it's not there. You'll have to wait until you get the hospital access card from the operating room in 1F. In order to get this card, you will have to go to 2F and jump out the window to land in the 1F Courtyard to find the key to the lockers.
Return to the locker room next to the staff room in 2F. The access card is in one of the lockers. Go back down to 1F, and enter the Operation Room to find a note indicating the following combination: 9 clockwise and 3 counterclockwise.