Measuring bosal 2
Horsehead skeleton redline
Horseshead redline bosal position
Jon bailey 19

The internal depth (A) of the bosal can range from 10” to 12+", however the average depth is around 11” - 11.5”. The width (B) will also vary from 4.5" - 6" pre shaping. Significant adjustment is possible with the use of a shaper and the wrapping of the mecate which can be used to shorten the bosal however this will impact on the balance. In some situations it may be necessary for a bosal with longer cheeks and even a wider nose button due to the make up of a horses profile e.g. deep jawline and breadth of muzzle.

Our Bosal average depth and width (before shaping):






5/8" (Extra Deep)12"-12.5"5"-6"6"-6.5"
5/8" (Standard)11"-11.5"5"-6"6"-6.5"

Position of the Bosal

The position of the bosal is approximately halfway between the horse’s muzzle (top of nostril) and bottom of its eye. The nose button of the bosal sits on the nasal bone above the soft cartilage (Ref Images). It does not want to be positioned on the soft cartilage. This is the preferred position however due to the individual profile of a horse, combined with the variation in a braided bosal then that may not always be achievable. A 11" internal depth may be insufficient for a cold blood but suit a warm blood and as a result the bosal may sit lower closer to the cartilage and chin as opposed to further up the nose bone and under the jaw. The best way is to find the ideal position and then to measure the circumference which will provide an indication to the internal circumference of the bosal although in reality it would need to be bigger than this to allow freedom of movement.

Once the mecate are attached and without contact the bosal and bars are angulated coming behind the corner of the mouth and close to the jaw line with the heel knot resting close to the chin of the horse. There should be space above the top wrap to ensure that there is freedom of movement and without irritation, the horse needs to be able to open its mouth. Then when taking a contact and pulling the bosal towards you the heel knot should be approximately midway along the jaw. The bars of the bosal should rest lightly on the side of the upper and lower jaw (not pinching). The lower the bosal is positioned amplifies the point of flexion, the higher the bosal and closer to the poll reduces this along with the sensitivity and feel for both the horse and rider.

When a contact is taken the nose button should roll evenly across the nasal bone of the horse with the bars coming into contact with the lower jaw. This balanced motion will become all the more minimal throughout the horses training. The horses profile will determine the ideal fitting. A bosal can be shaped (see shaping) to the contours of the horse however if the horse has a deep jaw (more cold blooded) then certain bosals may be too small and prohibit sufficient movement. We offer a broad range of bosals of varying dimensions from shorter nose buttons (see nose button) to greater internal depths, to help cater for all types of horses from quarter to draft horses.

The side buttons beneath the nose button should not pinch the horse but rest as the cheeks against the side of its head. They should be braided to secure the hanger/headstall between the button and the nose button but not prominent enough to create a sore point on the horse.

If a horse has a smaller jaw and the bosal appears too large then the cheeks can be shaped accordingly and the mecate used to reduce this depth, there should always be space between the top wrap of the mecate and the horses lower jaw. Additional wraps of a mecate will impact on the balancing, and release of the bosal as the heel knot will be carrying a greater weight.

The use of headstalls and hangers can be combined with a bosal without impacting on the release. If using a heavier weight thicker headstall there are a few considerations; the loop size (sufficient diameter, flexible enough to adjust), type of tie (latigo/buckle), cheek diameter (e.g. large diameter ¾” or ½”) and the button size. Latigo ties are preferable as they provide greater adjustment to permit movement without too much movement. Overtightening will impede the release of the bosal. If incorporating a fiador then a headstall is required (see fiador fitting).

The selection and fitting of the hackamore is a much discussed topic and we would like to state that the criteria may differ from one area to another, where different concepts of how the hackamore is traditionally used. At the end of the day it is paramount that it does not incur any damage to the horse, we fit and advise the purchase of our hackamores to customers based on them and their horse’s requirements and how we believe it will work best. Remember though body position, light hands are the key and heavy hands, poor posture combined with ill-fitting tack can impair training and create discomfort.