An adjustable guide apparatus for guiding filamentary material from a reciprocating traverse onto a mandrel of a winding machine to form a coil. The adjustable guide apparatus includes a housing having a collar defining an inlet opening configured to receive filamentary material, and adjustable guides coupled to the housing defining a guide opening between the adjustable guides for passage of the filamentary material from the inlet opening. The apparatus also includes an adjuster configured to adjust relative spacing between the adjustable guides that defines the size of the guide opening.