Sniper Ghost Warrior 3

WARNING

This trophy is not glitched, but it can SCREW YOUR SAVEGAME.

The trophy is awarded for getting all sidearms, and this can be obtainable by doing all the sidemissions and main missions, and also finding them in some places in the map which have the question mark.

I suggest that you buy the weapons as soon as you earn them, dont wait till having all of them just in case a glitch happens locking all.

Also, when you only have one weapon remaining locked, DONT PROGRESS ANY FURTHER. Quit to main menu, then quit to dashboard, and save the savegame on a pendrive.

Then, when you unlock the last weapon and buy it, chances are that the trophy is not going to pop. Quit to dashboard, and you'll earn it in the title screen. But there can be three things that can happen:

1) Savegame corrupt, even if the game don't tell you so (Continue campaign will be no longer, instead new game)

2) Savegame is ok, but all equipment you've earned through the game is LOCKED.

3) All is fine (This is the more unlikely to happen)

Here is where the savegame in the pendrive comes into play. Copypaste it over the savegame in the PS4 HD, and progress normallly through the game.

Good luck.

PS: In addition, here is a brief list of where to get the weapons to the achievement. Credit to this list goes to IGN Wiki

Main Storyline

M1984 Pistol
Herrvalt 99
Garett M9
Wagram 21
SLP .45

Side Missions

M1984 Pistol Rail - Side mission Rotki Lions 2
Bull 686 - Side mission Burning Bridge 2
SP M23 - Side mission Loose Ends 3
Sawn-off Shotgun - Side mission Opium Wars

Hidden Weapons Crate

MP-40 Grad