How do you introduce a new bit to a horse that has only known one type of bit?

Introducing a new bit — whether transitioning from snaffle to curb, from one curb to another, or from a hackamore to a bit — requires the same systematic approach that Clinton Anderson applies to introducing any new equipment: give the horse time to accept the equipment first, then introduce the communication through the new equipment before making any demands. Anderson's introduction sequence begins with putting the new bit in the horse's mouth and allowing the horse to stand quietly while it acclimates to the different weight, balance, and feel in its mouth. Different bits feel dramatically different — a loose ring snaffle moves freely and feels light, a fixed-ring snaffle feels more stable, a curb with shanks swings with the horse's head movement in a way a snaffle does not. Each change requires adjustment time. He then picks up the reins very softly with the new bit — lighter contact than he would typically use — and asks for basic, familiar exercises the horse knows well: walk, halt, flex. He is not trying to train anything new; he is translating familiar communication through the new equipment and watching how the horse responds to the different feel. If the horse braces, he checks whether the bit fits correctly before assuming the brace is behavioral. Warwick Schiller adds that the horse's first experience with a new bit is disproportionately important. A horse that experiences the new bit with heavy, confusing rein contact from the beginning forms a negative association that can take many sessions to overcome. A horse that experiences the new bit with light, familiar communication forms a neutral-to-positive association, and the adjustment to the new feel happens quickly.