schon shaft design?

[doubletrouble]

bought a used schon with a brand new 13mm shaft on ebay. certain it is a schon shaft. the thing is the tip and top portion of ferrule measure 12.75mm and the bottom portion of ferrule and beginning of shaft measure 13mm. don't mind no biggy. but just curious is this schon usual design of shaft? or in a sense a defect?

 

[treed]

shon ferrule

someone has tapered the ferrule,probaly by a new tip installation,or maybe by just cleaning.ferrule should be close to13mm the entire length.

 

[doubletrouble]

thanks

thanks for answer. somehow didn't happen to think of the obvious most likely reason.