A snaffle bit is the most common type of bit used while riding horses. It consists of a bit mouthpiece with a ring on each side and acts with direct pressure. A bridle utilizing only a snaffle bit is often called a "snaffle bridle", particularly in the English riding disciplines. A bridle that carries two bits, a curb bit and a snaffle, or "bradoon", is called a double bridle.
A snaffle is not necessarily a bit with a jointed bit mouthpiece, as is often thought. A bit is a snaffle because it creates direct pressure without leverage on the mouth. It is a bit without a shank. Therefore, a single- or double-jointed mouthpiece, though the most common designs for snaffle bits, does not make a bit a snaffle. Even a mullen mouth (a solid, slightly curved bar) or a bar bit is a snaffle.
The snaffle bit works on several parts of the horse's mouth; the mouthpiece of the bit acts on the tongue and bars, the lips of the horse also feel pressure from both the mouthpiece and the rings. The rings also serve to act on the side of the mouth, and, depending on design, the sides of the jawbone.[1]
A snaffle is sometimes mistakenly thought of as "any mild bit". While direct pressure without leverage is milder than pressure with leverage, nonetheless, certain types of snaffle bits can be extremely harsh when manufactured with wire, twisted metal or other "sharp" elements. A thin or rough-surfaced snaffle, used harshly, can damage a horse's mouth.[2]
Curb chains or straps have no effect on a true snaffle because there is no leverage to act upon. English riders do not add any type of curb strap or curb chain to a snaffle bit. While some riders in western disciplines do add a curb strap to the rings, it is merely a "hobble" for the rings, has no leverage effect and is there only as a safety feature to prevent the rings from being pulled through the mouth of the horse, should the animal gape open its mouth in an attempt to avoid the bit, an outcome prevented in an English bridle by the presence of a cavesson noseband.
See also: Curb bit and bit shank. The snaffle differs from the pelham bit, the curb bit, and the kimberwicke in that it is a non-leverage bit, and so does not amplify the pressure applied by the reins. With a snaffle, one ounce of pressure applied by the reins to a snaffle mouthpiece will apply one ounce of pressure on the mouth. With a curb, one ounce of pressure on the reins will apply more – sometimes far more – than one ounce of pressure on the horse's mouth.[2]
There are many riders (and a remarkable number of tack shops) who do not know the true definition of a snaffle: a bit that is non-leverage. This often results in a rider purchasing a jointed mouthpiece bit with shanks, because it is labeled a "snaffle," and believing that it is soft and kind because of the connotation the snaffle name has with being mild. In truth, the rider actually bought a curb bit with a jointed mouthpiece, which actually is a fairly severe bit due to the combination of a nutcracker effect on the jaw and leverage from the shanks.
A true snaffle does not have a shank like a pelham or curb bit. Although the kimberwicke appears to have a D-shaped bit ring like a snaffle, the bit mouthpiece is not centered on the ring, and thus applying the reins creates leverage; in the Uxeter kimberwicke, there are slots for the reins placed within the bit ring, which allows the reins to create additional leverage. Both are used with a curb chain, thus the ring acts like a bit shank and creates a slight amount of leverage, making it a type of curb bit.
A true snaffle also will not be able to slide up and down the rings of the bit or cheekpieces of the bridle, as this would place it in the gag bit category.
See main article: bit mouthpiece. The mouthpiece is the more important part of a snaffle, as it controls the severity of the bit. Thinner mouthpieces are more severe, as are those that are rougher.
See main article: bit ring.
There are several types of rings that affect the action of the bit.
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