List of all the weapons in MW3. 
Primary.
Assault Rifles.( Pictures and in

M4A1


M16A4

3 round burst



SCAR-L



CM901



TYPE 95

3 round burst
G36C


ACR 6.8


MK14




AK-47


FAD


Sub machine guns.


MP5


UMP45


PP90M1


P90




PM-9



MP7


Light machine guns.

L86 LSW

MG36


PKP PECHENEG


MK46




M60E4


Sniper Rifles

BARRETT 50CAL



L118A


DRAGUNOV


AS50



RSASS



MSR


ShotGuns.

USAS 12


KSG 12

SPAS-12


AA-12


STRIKER




MODEL 1887




Secondary Weapons.

Machine Pistols.


FMG9



MP9


SKORPION


G18



Handguns.

USP .45


P99


MP412

44 MAGNUM


FIVE SEVEN


DESERT EAGLE



Launchers.

SMAW


JAVELIN


STINGER

XM25


M320 GLM


RPG-7



Weapon Proficiencies.
KICK

Reduces weapon recoil.

IMPACT

Increases bullet penetration. This works just like the FMJ attachment in MW2.

ATTACHMENTS

Allows two attachments to be added to the weapon.
FOCUS

Reduces flinching when you get shot by the enemy.

SPEED

Increases your speed when you have the weapon equipped. This only works with Light Machine Guns and Sniper Rifles.

BREATH

Allows you to steady your weapon by holding your breath for a limited time.

STABILITY

Reduces weapon sway when aiming.

RANGE

Increases the weapon's range. Doesn't work with Light Machine Guns or Sniper Rifles. 

MELEE

Faster melee, but only works with Sub Machine Guns.


DAMAGE

Increases damage. Shotguns only.
Lethal
FRAG
Cookable fragmentation grenade that causes lethal radius damage.

SEMTEX
Works just like the FRAG, but it sticks to the first thing it touches, including other players. It has a set timer and cannot be cooked.

THROWING KNIFE
The THROWING KNIFE is a one-hit kill. The knife can be retrieved and used again.

BOUNCING BETTY
When triggered, the BOUNCING BETTY launches into the air and explodes. The blast can be avoided by going prone quickly.

CLAYMORE
Anti-personnel mine that's triggered once the enemy gets close to it.

C4
Charge of plastic explosives, set off manually with a detonator.

Tactical
FLASH GRENADE
Temporarily blinds the enemy.

CONCUSSION GRENADE
Slows enemy movement and also disorients them. It can also be used to temporarily disable enemy equipment and turrets.

SCRAMBLER
Once deployed, it scrambles the enemy radar within its effective radius.

EMP GRENADE
Destroys enemy equipment and electronics within its blast radius.

SMOKE GRENADE
Creates a thick smoke screen.

TROPHY SYSTEM
Once deployed, it deflects explosives, e.g., missiles that are launched at its direction.

TACTICAL INSERTION
Once deployed, you can respawn on it after you die. The TACTICAL INSERTION can be destroyed by the enemy.

PORTABLE RADAR
Shows enemy movement within its radius once it has been deployed.