Call of Duty MW2 and MW3 weapons:

FAMAS
M4A1
M4A1
M16A4
Vector
ACR
MG4
MP9
MG36
Striker
SPAS-12
MK14
CM901
PP90M1
FAD
SCAR-L
AA-12
MK46
MP7
USAS 12
MP5
UMP45
M60E4
PKP Pecheneg
KSG 12
Skorpion
AK-47

Call of Duty MW2 and MW3 guns and snipers:

Intervention
Barrett .50cal
.44 Magnum
Desert Eagle
Desert Eagle
MSR
L118A
RSASS
AS50
Five Seven
USP .45
P99

Maps:

Bloc
Bog
Countdown
Downpour
Overgrown
Pipeline
Shipment
Showdown
Strike
Wet Work
Creek
Killhouse

Install:

Create a shortcut to cod4 (iw3mp.exe) and rename to: Steam and paste it on the (Game) folder.

Paste it on the cod4 installation folder, it's on Call of Duty 4\Mods\(Extract the mod and just paste it), Open MW2_MW3.exe, choose your custom weapons, load it on the game menu, Mods\MW2_MW3. Have fun