I just tried a C/C tip section on a PST (middle) section (14' rods) ... and "yes", it will go in. BUT, it actually goes in much farther than it does on a C/C middle section ... by a couple of inches (~3"). It does seem to be sufficiently secure when inserted, but without actually fishing with that combination, I can't really say for sure. I know that I wouldn't "force" the PST middle section into the C/C tip section, for fear of fracturing either one of the two section's ends.

FWIW -- a PST tip section will fit (snuggly) onto a C/C middle section ... and at the correct depth into the blank. Again, without actually fishing with that combination, I cannot say how the combo will perform.

My PST & C/C rods are a couple of years old, so I'm not sure if either model has had any changes in any newer models.