Injection molded articles and mold apparatuses for forming same

A mold core for forming an injection molded article, comprising:

• a) a first mold surface having a thread mold extending helically about a core axis for forming internal threading in an article first portion of the molded article;
• and
• b) a second mold surface spaced radially apart from the first mold surface, the second mold surface for forming an article second portion spaced radially apart from the article first portion and connected to the article first portion by a connection portion, and the second mold surface comprising at least one rib mold feature for forming at least one ejection-assist rib of the article second portion, the ejection-assist rib having a helical slide surface extending helically about the article axis, wherein during an initial unscrewing rotation of the molded article relative to the mold core, the rib mold feature bears against the helical slide surface to urge the article second portion axially away from the mold core during ejection of the molded article.