Tom,
"A little" looseness is not uncommon. As you said the pin that holds the buttcap on is keeping it from moving, but the deminsions of the stacked leather handle has shrunk. Usually this happens if the knife has been in a very dry environment.
However, if you feel it is excessive, we will be more than happy to take a look at it for you. If so, please contact customer service @ 800-344-0456.
Thanks for being a customer!