Bradford began the tie by scoring an early try as Matt Ryan barged over the line before Ryan Shaw added the conversion, though Tommy Saxton replied for Halifax soon after by diving over after interplay between Tryer, who added the conversion, and Ben Johnston.
Tryer then went over the line himself after catching a cross-field ball from Scott Murrell, adding another conversion to give Halifax a six-point advantage after 16 minutes.
Shaw hit back for Bradford in the 30th minute as he collected a kick-through to record a try, then converting once more, before repeating the process minutes later to put the Bulls back in the driving seat.
Dane Manning responded with a Halifax try just before the half-time whistle, though Tryer could only find the post with his conversion as Bradford went into the half with a two-point advantage.
Saxton went over for his second early in the second half, which Tryer converted, before recording his second try after 59 minutes.
Johnston then scored two tries for Halifax in the space of four minutes, both of which were converted by Tryer to give Richard Marshall's side a 20-point lead.
Tryer converted Heaton's score before completing his hat-trick by diving over after a field-long break.