He has recently improved greatly, and the reason is easy to spot. I checked over his tack one day as I was tacking him up and realized that his bridle was much too tight around the ears. It simply did not fit. I talked to my instructor and we found a spare bridle that fit much better. The change was incredible after that. He became much more responsive and so much happier. Last week I took him over a full hunter course with lines and diagonals and managed to keep control of him the entire time without him racing away at top speed. That NEVER would have been possible before.
However, his jumping still remains an issue. Although I can keep control of him, I sometimes feel like I am being too hard on his mouth. I've discovered that the way to keep him at a good pace after a jump is to ride up to the jump with my hands slightly farther up the neck that normal (though not pulling on his mouth). I half-halt to gather him as I establish my pace, however I don't once I am aligned with the jump, as not to upset his striding. Once I go over, I immediately collect him with a slight upwards half-halt after the first stride so that he does not have a chance to change the position of the bit in his mouth. I then follow with as many half-halts as needed to collect his pace afterwards until it is controlled and even (which is usually about 2 more). I find that when he puts his head down he prepares to get off the bit as soon as I release all rein contact, such as over a jump.
Sometimes I feel like I'm pulling TOO much though. I feel like all these half-halts and all this pulling on his mouth must really bother him. Also, I've had him gallop away with me twice before in the middle of a jump-filled arena, and it's pretty scary moving that fast and seeing jumps pop up everywhere you turn, while the horse I'm on is irrational and panicking. Even worse, he's gotten injured both times. Nothing too serious, but still. That was before I switched his bridle, so I know things are a lot better now for me and for him, but I think I still worry about it sometimes. I know I don't really trust him that much.
So I guess I have two major questions. 1. How can I keep him from racing away after the jumps and getting off the bit while not using too much rein, and 2. How can I build up a better trust relationship? He needs to be able to trust me (he does already, considering he's one of those horses who only responds to people he likes and trusts, but I don't think he trusts me 100%) and I need to be able to trust him.
Thanks, everyone, and sorry for the really long post!!