What does a figure 8 noseband really do?

I've read many forums, but no one has written a good answer:
My horse and I do jumpers, specifically level 0's and 1's, but anyways, I need an easier way to turn, with out putting her on a harsher bit. She turns quite nice, but I feel we could do better. So I was looking into the figure 8 nosebands', and some forums say they distribute the pressure across their face.. Is this true? I want to order one soon.. So please help?

I've heard their main purpose is for show (which isn't a very good reason IMO) and to keep the bit in a certain spot. Often this "spot" is a place that keeps constant pressure on the mouth even if the reins are completely slack. At my barn one horse has a figure 8, and apparently its because "it helps him keep his head down." Its really just because the bit is just constantly pulling on his mouth. Another thing I've heard is that the horse doesn't drop the bit, but with a properly fitted bridle they shouldn't be able to do that.

I honestly don't think a figure 8 will help what you want to accomplish. I think lots of ground work will help loads, though.

In dressage, at the lower levels, a flash noseband, not a figure 8, does help keep the bit, usually a loose ring, in its proper, effective position in the horse's mouth.

In jumpers and event horses, a flash or figure 8 is using to prevent the horse from opening its mouth and bracing its lower jaw on the bit. The horse is still free to evade the bit by other methods, such as raising its head above the bit or going behind the bit.

In neither usage is it correct to tighten the noseband so much that the horse's mouth is effectively tied closed; if the horse cannot still mouth or chew the bit then the noseband is no longer effective and becomes counter productive.

Nothing about using the noseband improves turning ability unless the horse has the habit or bracing and resisting on the turn; since a noseband doesn't normally apply pressure to the horse's face there's no need to redestribute pressure. (The exception would be a kineton noseband, which converts some bit pressure into pressure over the bridge of the nose - fairly rare, I've only seen then in books and photos)

Tymer, I am not familiar with any of the information you've posted, it almost sounds like you're confusing a figure 8 noseband with a running martingale?

Nosebands of any kind do not:

1.) keep constant pressure on the mouth even if the reins are completely slack.
2.) keep the horse's head down. (except perhaps a racehorse shadown roll)
3.) keep the bit constantly pulling on the horse's mouth.
4.) keep the horse from dropping the bit.

I'm also a bit vague on how doing lots of ground work will improve a horse's ability to make tighter or more accurate turns on a jumper course.

Rereading my post, yes, I was quite vague.
What I have been taught is that it keeps the bit in their mouth. I messed up and said it will put constant pressure on the bit, but I was mistaken. I meant that keeps the bit on their mouth, which may irritate some horses. Its not exactly pulling. I don't mean drop the bit in a dressage way, but more in a literal way, as if the bridle is too large.
I don't mean plain old ground work, I meant work on turns and bending and such, but I hoped that was understood.
I apologize for any incorrect information or miswording in my other post. I'm tired and it has not been the greatest day for me, not to mention I am still learning.

Edit: Oh, I forgot one thing. The head down part was something I was told that I do not believe. I believe it was because it helps increase the bit's pressure...? I may be confusing it with the reasoning they gave me for using the elevator bit....Which would be head raising. Augh, I'm tired.

The grackle or flash noseband are very useful when a horse twists its jaw to avoid work.

My first pony was an expert at this and because I was tiny I had very little hope of stopping him when he did. He would twist his jaw, set his neck and just go. He was ridden at home in a flash noseband. It was taken off at shows after the warm up and put back on immediately after the class (they are not allowed in ridden showing over here) he was fine for the time it took to do the class.
He had learnt he could do it and top class trainers couldnt get him to stop doing it!

I believe I read somewhere that one benefit of the figure 8 noseband, and this applies to the dropped noseband also, is that it has no contact or pressure at the place on the horse's jaw where a typical noseband does, and the problem with a typical noseband for some horses is that some have teeth that angle outward at that point in their jaw and the noseband squeezes the soft lip tissue right against the sharp teeth edges. A figure eight would avoid that area. (that area being just behind the bars on the jaw)

I love... love... my figure eight. Try it. You will be able to make your own educated decision on it. :)

I was recommended a figure 8 nose band for my mare because she grinds her teeth by moving her jaw side to side. The trainer suggested that as soon as she was a bit softer with a bit to stick her in a figure 8 to stop the grinding and wearing her teeth.

I found out what was causing the grinding and didn't need to use it, and my current trainer hasn't mentioned anything about teeth grinding, so I think the problem was solved. (It was a tell for pain and confusion)

The figure 8 noseband keeps the horse from crossing his jaw or opening his mouth too far... but it also allows for easier air flow through his nasal cavities. I've found that several horses like the figure 8 better then a flash for that reason.

The figure 8 will NOT help your horse turn better. It will have very little effect (if any) on turning ability. The reason is because when you want a nice balance, tight, fast turn for the jumper ring, you need to ride the horse's hind end. Changing up a noseband implies you're riding his front end. The best thing you can do is get your horse strong and balanced using his haunch. Shoulder in, Shoulder fore, Haunches in, Counter Canter, etc etc. Those are the exercises you want for a really effective jumper ride.

I'm assuming you're talking about a Mexican or Grackle noseband?
If so, I definitely prefer the Mexican over the Grackle. Though, in my opinion either of them is loads better than a flash noseband.

While their concept is similar, the Mexican is far more effective than the Grackle.

Both nosebands prevent the horse from setting or twisting their jaw to evade the bit and commands given by the rider.

The Mexican is more ergonomically shaped to distribute pressure evenly across the horse's face. Because nosebands *do* apply pressure. Maybe not as much as certain bits apply pressure to the poll, or in an earlier example, the kineton noseband.

For a noseband to be truly effective, it has to be done up firmly. IE: The top part - whether it's a cavesson or grackle (figure 8) should not have any 'give' to it. The lower part or flash, should be 'loose' enough to fit your index finger under.

No item of tack can *ever* make a horse turn more effectively, or respond to a rider's aid or instruction. That part comes down to correct schooling on the flat. A Grackle or Mexican noseband can help with the process, but really, if you want your horse to be quicker with it's turns, you need to work on your schooling work at home. Lots of upward and downward transitions, figures of eight and serpentines, circles and half circles. The horse should be working off your seat and legs, not your hands.

EDIT:
In the attachments, the picture on the left is of a Mexican Noseband, and the picture on the right is a Grackle Noseband. The Grackle is more similar to a regular flash noseband in terms of how it sits on the horse's face. (sorry I couldn't find a better picture). I prefer the Mexican style because (as has already been mentioned) it avoids that sensitive area of the jaw, and also because it's more effective in preventing the jaw from twisting.