In Call of Duty: Modern Warfare 3 for the PC, PS3, Wii, and Xbox 360, most unlockables in Survival Mode unlock as you progress in levels. You start with basic maps, weapons, and equipment, and everything else is unlocked as you gain levels.
Here are all of the unlocks in Survival Mode, and what level you must reach to unlock them.
Levels
Tier 1 Levels – Easy difficulty, unlocked from the start
Interchange
Resistance
Underground
Village
Tier 2 Levels – Regular difficulty, unlocked at level 8
Carbon
Dome
Mission
Seatown
Tier 3 Levels – Hard difficulty, unlocked at level 15
Bootleg
Fallen
Hardhat
Outpost
Tier 4 Levels – Insane difficulty, unlocked at level 25
Arkaden
Bakaara
Downturn
Lockdown
Air Support
Predator Missile – $2500
Air Strike – $2,500, unlocked at level 4
Delta Squad – $3,000, unlocked at level 14
Riot Shield Squad – $5,000, unlocked at level 21
Attachments
Scope Attachments
Holographic Sight – $1000, unlocked by default
Red Dot Sight – $750, unlocked at level 7
ACOG Scope – $1250, unlocked at level 30
Under-Barrel Attachments
Grip – $750, unlocked at level 19
Grenade Launcher – $1500, unlocked at level 28
Shotgun – $1500, unlocked at level 45
Equipment
Claymore x5 – $1000 (limit of 10), unlocked at level 2
C4 x5 – $1500 (limit of 10), unlocked at level 3
Body Armor – $2000, unlocked at level 10
Self Revive – $4000, unlocked at level 12
Sentry Gun – $3000, unlocked at level 17
RPG-7 x2 – $2000 (limit of 4), unlocked at level 27
Sentry Grenade Launcher – $4000, unlocked at level 31
Riot Shield – $3000, unlocked at level 37
Perk Care Packages
Quickdraw – $3000, unlocked by default
Steady Aim – $3000, unlocked at level 8
Stalker – $4000, unlocked at level 22
Extreme Conditioning – $4000, unlocked at level 36
Sleight of Hand – $5000, unlocked at level 50
Weapons
Assault Rifles – Cost $3,000 each
M4A1 – Unlocked by default
M16A4 – Unlocked by default (starting weapon on Tier 4 maps)
SCAR-L – Unlocked at level 5
ACR 6.8 – Unlocked at level 14
AK-47 – Unlocked at level 24
FAD – Unlocked at level 32
G36C – Unlocked at level 39
CM901 – Unlocked at level 43
MK14 – Unlocked at level 47
Type 95 – Unlocked at level 50
Handguns – Cost $250 each
Five Seven – Unlocked by default (starting weapon on Tier 1 maps)
USP. 45 – Unlocked by default (starting weapon on Tier 2 maps)
MP412 – Unlocked at level 2 (starting weapon on Tier 3 maps)
Desert Eagle – Unlocked at level 11
.44 Magnum – Unlocked at level 20
P99 – Unlocked at level 40
Light Machine Guns – Cost $7,000 each
M60E4 – Unlocked at level 12
PKP Pecheneg – Unlocked at level 18
MK46 – Unlocked at level 34
L86 LSW – Unlocked at level 41
MG36 – Unlocked at level 48
Machine Pistols – Cost $1,500 each
G18 – Unlocked by default
Skorpion – Unlocked at lvl 3
MP9 – Unlocked at lvl 17
FMG9 – Unlocked at lvl 37
Shotguns – Variable Costs
Model 1887 – $2,000, unlocked by default
USAS-12 – $2,000, unlocked at level 6
SPAS-12 – $2,000, unlocked at level 16
KSG-12 – $2,000, unlocked at level 26
Striker – $4,000, unlocked at level 33
AA-12 – $5,000, unlocked at level 44
Sniper Rifles – Cost $2,000 each
MSR – Unlocked at level 7
Dragunov – Unlocked at level 16
RSASS – Unlocked a level 29
L118A – Unlocked at level 35
AS50 – Unlocked at level 42
Barrett .50 Cal – Unlocked at level 49
Sub Machine Guns – Cost $2,000 each
MP5 – Unlocked by default
UMP45 – Unlocked at level 4
MP7 – Unlocked at level 13
PM-9 – Unlocked at level 23
PP90M1 – Unlocked at level 38
P90 – Unlocked at level 46