is there a hk416 or xm8 in modern warfare 2 ?

[FastFord58]

Well, the XM8 is a canceled project and only exists in prototype form. Not sure about the other one.

 

EDIT: The HK416 looks to sililar to an M4 to lend it any visual distinguishablility within the game. People who don't specifically know about weaponry would probably see it as a redundant weapon.