p22 p22q target barrel

Hello! I was hoping somebody could tell me what the internal dimensions are for the P22 Target's compensator. In other words, how wide is the opening through which the barrel and barrel-sleeve pass? Thanks! Mike

Ok, two things; I can't seem to figure out from the Internet, what the difference between the P22 and P22Q is, other than the grips. Is there any real engineering difference that would cause parts to not be interchangeable between the two models? Which leads to the second question. If I pick...