I figured out a long time ago that, for me, the best way to train a horse out of bucking under saddle was to go in a roundpen and make the horse run. I usually put a western saddle on so I can have a good seat. I find that when a horse is running around and tries to buck, they will basically almost fall on their heads. They always save themselves but it is self correcting. I stay out of the way so the punishment for bucking is all on them. It has worked for many horses over the years, but now I'm curious.
What other ways do people get a horse out of bucking?
My old trainer used to smack them with a crop when they bucked, but that seemed counter-productive seeing as they then bucked from the whip.