Hackamores and Bitless Bridles
A hackamore, put simply, is headgear that controls a horse via pressure points on the face, usually with a nosepiece instead of a bit. A hackamore is not the same thing as a halter, as a halter is primarily used for leading and tying up an animal. Bitless bridles are similar to hackamores, but some designs use different leverage principles for control. Hackamores and bitless bridles use a headstall with reins attached to some type of noseband or nosepiece. Various designs allow control and good communication to the horse and may, in some cases, be more comfortable to the horse, particularly a young animal or one with a mouth injury.
The jaquima or original bosal style hackamore is mostly seen on young horses being started under saddle in western riding disciplines. Bitless bridles and other types of hackamore are most often seen on horses used for endurance riding and trail riding. A design called the mechanical hackamore is sometimes seen at rodeos. Most horse show events do not allow bitless bridles of any kind. The exceptions are show jumping, where equipment rules are fairly generous, and in certain western horse show classes for "junior" horses, which permit use of bosal hackamore.
Besides the bosal hackamore, there are many other designs. A design that combines elements of the bosal hackamore is known as a sidepull, which acts mostly on the nose, and are popular with western riders and many trail riders. English riders sometimes use a jumping cavesson or "jumping hackamore" that is basically a leather sidepull noseband reinforced internally with a cable, with rein rings attached. The so-called mechanical hackamore or "hackamore bit" is basically a hybrid bridle/hackamore made up of a noseband with shanks and a curb strap or chain that can put considerable leverage on the jaw and poll.
Another design, called a bitless bridle is the "cross-under" or "figure eight" bridle. One common design connects the reins to a loop that passes from the noseband, under the jaw, and up around the poll, returning on the opposite side back under the jaw to the noseband and out to the other rein. This design directs pressure from one rein to the opposite side of the horse's head, or pressure on both reins to the whole head. Other designs only cross under the jaw and do not go over the poll.
Some riders, not realizing that a horse's head overall is a very sensitive area, use a noseband-based style of headgear without the same caution they might use with a bit, thus defeating any benefit that an apparently milder form of gear would otherwise provide. While many bitless designs are marketed as humane, and some are indeed quite mild, other designs can be remarkably harsh in the hands of a poor rider, particularly if they are improperly adjusted or have metal parts, a thin design, or rough surfaces.
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