Each time you rank up or obtain certain badges in multiplayer, you unlock new weapons. These weapons are unlocked for Multiplayer use only. Guns are listed in order, Team 1 weapons first and Team 2 weapons second.

Effect	How to unlock
33 SC-1 and SG-76 H-Bar (Snipers)	Achieve rank R2
AR-15 and Draugonov (Snipers)	Achieve rank T2
Claymore Mines	Earn Expert Gadget Expertise Badge
Desert Sniper .357 and SP-57 (Pistols)	Achieve rank O3
Double Sawn-Offs (Pistol)	Earn Elite One-handed skill badge
EMP Grenades	Earn Expert Explosive Expertise Badge
EPDD	Earn Elite Hand to Hand Combat Badge
G-17 and Makarov (Pistols)	Start a new account (R0)
Laser Mines	Earn Elite Gadget Expertise Badge
M16 A2 and Famas(ARs, burst fire)	Start a new account (R0)
M16K and Galil (ARs, Full Auto)	Achieve rank O2
M60 E-3 and Chinese Type-56 (HMGs)	Achieve rank O1
M67 Grenades	Earn Elite Explosive Expertise Badge
MDS A3 and Spectre (Full Auto SMGs)	Achieve rank R1
MDS-7 and Ripper (SMGs in pistol slot)	Achieve rank T1
Shot Defender and SPA-12 (Shotguns)	Achieve rank R3
Trip Bar and Ramat (HMGs/ARs)	Achieve rank T3
USAS-12 and Sawed Off (Shotguns)	Achieve rank 04