Yes you can get it as a secondary weapon but you have to unlock the perk overkill.
Yes, in Modern Warfare 2 you can get it as a secondary weapon
under your mamas bed
You go to "Create A Class" Then Primary or Secondary weapons to choose your weapon then after u edit your weapon.
It is all about how good you are with the gun.
It is Polysynaptic
go to create a class once you are a high enough level equip it as your secondary weapon
Reflex angle
m4,m16,ak47
a MAC 11 or an AK47
ak47
2000
Call of Duty: Modern Warfare: Reflex