Chewing the bits and snatching the reins

[Katie-gillingham25]

My 6 year old OTTB mare chews on the bit constantly when ridden (when lunged in a bridle she is completely still)
When ridden in an arena its not too bad. When hacking its almost unbearable. She will either put her head in the air or want it on the ground. She likes to snatch the reins a lot. Doesn't matter if I leave her alone or have contact. She likes to zoom forwards so I usually have to have some contact.
Everything has been checked, back, teeth etc. I have a bit specialist coming out (we have tried lots of different bits)
I have read about feeding Magnitude, I'm wondering if anyone has any experience with this being helpful? She gets very excited/anxious so wondering if it will help?

 

[Midlifecrisis]

I’m not sure magnitude will help if the problem is related to mouth comfort. I think a really good loriner is a great place to start. My apologies if you have covered this elsewhere but if she is recently off the track she may very well still associate a rider with being held quite firmly but being urged forward…and on the hack she is anticipating the signal to be off. The quiet head during lunging wouldn’t have that association. Having a good trainer on the ground witnessing the snatching would help…there is a possibility that how you maintain contact with the bit you are using is creating the behaviour.