Can you hook us up with some photos of these new mods?
Originally posted by para
Can you tell the barrel length? If it is an M16 it should be 20", as opposed to the M4's 14.5. Also, was it a Marine or Army unit? Some special operations units use a Knight's RAS/RIS or some variation thereof for mounting lights and the aforementioned vertical foregrips (which I believe make the rifle easier to control in CQB situations). If the Rangers went in with the Marines it could have been their rifles that you were seeing.
Don't take me at my word for any of this though, it's all just as I have come to understand it.
M4 SOPMOD - I know the ones you saw had A2 stocks, but this is a pretty standard special operations M4 with a RIS.
Knight's RAS