I have tried an eggbutt snaffle (which had previously been used with this horse), a d-ring, a loose-ring, and a full-cheek snaffle, but the mare shakes her head, halts, chomps the bit, swishes her tail, etc. This behavior begins once she has the bit in her mouth, even with no contact on the bit (although contact intensifies the behavior, especially if I am mounted and asking her to walk). I have tried various headstalls for fit reasons and this has not helped.
I have no idea if this behavior is truly due to the bit, or if the mare is just out of practice (only ridden a handful of times in the last year) and just balking a little at the work. It occurred to me that maybe I should go back to square one and try a bosal-type non-mechanical hackamore. I have never used one of these before, so I went to a local tack shop for advice. The woman there told me that nobody should use a bosal if they haven't used one before. This begs the question: how does anybody ever start using one?! Regardless, she told me "no" on the bosal and suggested we have the mare's teeth checked out, which we will do.
I ended up buying a thicker rubbery snaffle today, and I'm going to try that tomorrow. If the behaviors continue with the mare seemingly hating the bit in her mouth, what do you suggest? I've been told that I should remove the reins, put the bridle on the mare, put her in a stall, and let her get used to the bit that way. Is that recommended?
Does anybody have any advice for me? This is a "backyard" mare who is loved, well taken care of, and in good health. The owners simply haven't had time to ride her consistently. The mare is not working with a professional trainer, and it doesn't seem to me that one is necessary (this is not going to be a show horse, just essentially a trail horse). Nevertheless, the woman at the tack shop brought it up immediately, as if to say I shouldn't be riding this horse because I'm not a pro. I've been riding for 35 years, shown western please and hunt seat, owned three of my own horses over the years. I'm not an expert and I'm not a trainer, but I believe I have enough experience to slowly bring a green horse along. Or do I?