i ride him in an eggbutt snaffle
Do you or anyone else bang his teeth when the bridle goes in or comes out? When was the last time his teeth were floated? Were his wolf teeth pulled?
If his teeth were floated in the last 6 months and his wolf teeth were removed, then I would try using a flavored happy mouth bit with a roller or french link. Horse & Rider, ETC.: Happy Mouth Loose Ring Roller Snaffle HMouth King Dee Double Jointed Roller Mo and King Dees|EQUESTRIAN COLLECTIONS.COM HMouth Double Jointed Roller Full Cheek and Full Cheek Bits|EQUESTRIAN COLLECTIONS.COM HM Revolver Loose Ring Snaffle and Loose Ring Bits|EQUESTRIAN COLLECTIONS.COM
These instructions are assuming this is a learned behavior from previous fear or pain from improper bridling techniques. I've used this before on three different horses and it worked like a charm. Before you begin, you need to make sure your horse will calmly and respectfully take a treat from your hand.
Show him the bridle, but don't try and put it on. Instead, just put it over your arm and groom him. Once he's calm, give him a treat. Next hold the bridle against his neck. Just stand patiently until he calms down, then give him another treat. Next hold the bridle against the side of his head. Again, just be patient until he calms down, then give him a treat. Quit for the day with that.
Next day, do the same. Keep doing the above everyday until he's calm for all of it, then try holding against his forehead with the bit hanging below him, but don't put it in his mouth. Give him a treat once he calms down. Now do the above plus the bridle over his head until he's calm, lots of treats
Now, with the bridle on your arm near his face, but not against it, work on putting your finger or thumb in the corner of his mouth to get him to open it. Put some syrup or honey on your finger so he gets a taste when it goes into the side of his mouth. Once he'll let you do it without tossing his head, give him a treat and quit.
Continue the finger/thumb in the side of his mouth until he'll stand quietly for it.
Now you're ready to try to put it in his mouth. Do as above, holding it over his head. Pull it up gently so the bit is against his teeth, so he can feel the type of material the bit is made of. Treat him for standing quietly. You're next step is to put your thumb/finger in the corner of his mouth to get him to open it. Don't pull the bit in, just have him open his mouth with the bit right there. Treat him for allowing it without flinging his head around. Once he's good, try CAREFULLY sliding the bit in his mouth then letting it carefully drop back out. Treat him for it, even if he didn't stand still that great.
Again, do this daily until he'll let you put the bridle in and out of his mouth. Once he's calm for that, put the bit in and bridle him normally. Give him a treat for being good.