Abstract: An article is molded in a mold cavity where the article has a profiled bore extending axially therethrough which has a precisely centered small diameter bore section at one end thereof. A mold cavity is defined by lower and upper mold halves and has a cavity axis, and a core pin having a precisely centered needle-like tip section at the upper end extends upwardly from the lower mold half coaxially through the mold cavity. Its needle-like tip section extends into a precisely centered small diameter bore of a nose piece at the upper end of the mold cavity when the mold halves are closed. The nose piece can be adjusted vertically within the upper mold half to vary the distance the core pin tip extends thereinto to vary the length of the forward end of the molded article.