How to unlock the M16 in Modern Warfare 2 Unlocking weapons in Modern Warfare 2 is different from previous titles. Several weapons, such as the M16, are now unlocked by using and levelling weapons within families known as 'Platforms'. In the M16's case,  you have to use the 556 Icarus until it reaches level 12 . To unlock the Icarus to do this, you need to level the M4 to level 15. Quite the process! Once unlocked, you'll be ready to start levelling the M16 to open up its customisation options - it's best to use the M16 for a few matches to level it up and unlock its attachment slots. It's worth noting - many attachments are unlocked by levelling other weapons, both in and outside of the M4 Platform. Additionally, if you own the Vault Edition of Modern Warfare 2, you actually have a head start on this process thanks to the FJX Cinder Pack – with this pack, you'll have access to all the attachments and weapons unlocked within the M4 Platform. Modern Warfare 2