How do you like your CCS stock? I assume it's made for the Colt 9mm carbine as well.
The CCS uses a modified bolt carrier, so I don't know if it would work with 9mm. Does the 9mm use the same bolt carrier and spring as the .223? If so, it should work.
The stock does have a shorter length of pull, and it isn't the most comfortable to shoot, but it is pretty cool and it makes the gun shorter when collapsed.