Weapon mods.

[Sirbastage]

Do any weapons come with mods that require chips?

 

[Melliores]

Yep, some of the FAMAS rifles have an advanced scope on them. Also if you buy weapons from the vendors, most of them will come with an advanced scope as well. The Dragunov from the Poacher's camp (C5), comes with a Thermal scope for example.

[Uncle Nick]

+1 Just watched a player stream, and he says Famas when modded becomes like a 5AP Sniper rifle.