Learn How to Measure Bit Shank Length

shanklengthTo understand how any given shanked or curb bit will affect your horse’s response it’s important to understand how to measure the bit and what affect the measurements or, more accurately, the ratios of the measurements may have.

It’s also important to know how to measure the shanks of a bit to determine its legality in various horse show organizations. Rules for shank length can be found in the organizations rule book and generally are limited to 8 ½ inches.

A shanked bit is any bit that produces leverage when the reins are pulled. The leverage component of this type of bit categorizes it as a curb bit, regardless of mouthpiece. It has 2 main components: the shanks (cheek pieces) and the mouthpiece. Where the mouthpiece attaches to the shank is known as the butt. This is also the point of balance in any shanked bit.

The shanks can be more accurately divided into the purchase with bridle ring and the true shank below the butt of the mouthpiece with rein ring (picture 2). The length of the purchase and the length of the shank help determine the speed at which the horse’s mouth, curb strap groove and poll receive the signal from the bit when the reins are pulled or released. It’s important to remember a variety of other design factors, particularly shank angle, play a role in the effect of the bit on the horse’s mouth but here we’ll address lengths in shanks that otherwise are equal.

Whenever the reins are pulled the bit revolves around the butt or balance point. As the reins are pulled the rotation of the mouthpiece causes the bridle rings to move forward of the point of rotation and the shanks to move behind the point of rotation. This movement in turn causes the curb to be tightened on the chin and the crown piece of the headstall to put pressure on the horse’s poll. As the ratio of shank to purchase increases the leverage a rider has available also increases as does the speed of the signal.

For shank measurement purposes for horse shows and general bit descriptions an imaginary line is drawn on the inside of the bit from the point where the headstall is attached to the bit (picture 1, A), through the butt to the point where rein pressure is applied on the rein ring of the bit (picture 1, B). The bit shown here has 7 ½ inch shanks.

Dennis Moreland bits are handmade in the shop by bit makers who have years of experience. To learn more take a look at our bits here: or call 817-312-5305. Since we ride and show regularly we have a good idea of which bit will work well in which situation. We make a wide variety of horse bits to fit the needs of almost everyone. These include snaffles, steel swivel and solid shanked bits, swivel aluminum shanked bits, Spanish bits and gag bits.

All steel bits are made from high grade 4130 steel and accented with beautiful yet very durable hand engraved nickel silver overlay. The mouthpieces are steel with copper strips to promote salivation.

We’re a full line manufacturer of handmade tack and we’re here to help you!