What is a Pseudo-Gag?

Firstly, we need to understand what the gag action is: gags primarily raise the mouthpiece up in the mouth, pulling the lip up, often quite a lot, using a loose ring attachment of the mouthpiece to the cheek, and they use leverage to apply pressure to the poll. And yes, these are conflicting signals to the horse.

So a pseudo-gag is a bit that is not technically a gag but has very similar pressure point results for the horse. Pseudo-gags are bits that have a fixed mouthpiece, which is why they don’t fall into the broad gag category, and they have a 1:1 ratio between the length of the shank of the bit and the length of the purchase, so they are the same length. When the rein is pulled, the bit rotates and the mouthpiece pulls the bit up in the mouth, stretching the lip, and applying pressure on the poll - hence the ‘gag’ action without it actually being a gag bit.

Now you may be wondering why that 1:1 length ratio is important or why all leverage bits don’t create a pseudo gag action, so here is some fun high-level physics to help explain.

The best way to think of leverage bits is like a see-saw with a pivot point, or fulcrum, in the middle. With a bit, the pivot is the mouthpiece. So when the bit has a 1:1 ratio of purchase and shank length, there is no amplification of the rein pressure or leverage effect. When the rein is pulled, the bit rotates around, and because the forces down the rein and bridle are equal, the primary outcome is the mouthpiece rising in the mouth for the length of the purchase.

Now, when we double the length of the shank compared to the purchase, so we are now at a 2:1 ratio, the amount of pressure felt through the bit is two times that of the pressure put down the rein. So the primary action of the leverage is to pull down the bridle cheekpiece and apply pressure at the poll. There will be a small amount of lifting of the lip still, but not the stretching of the lip that gags do.

We have talked about these bits in their purest form and not with using curb straps; all bits with a leverage action should be used with a curb strap. Another thing to note is that when the purchase is set back at an angle, the poll pressure forces are delayed, but angles of purchase and shanks are maybe a topic for another day.