I am not a huge fan of tom thumbs....they seem to pinch my horses mouth. Have you tried using an argantine bit, maybe one with a twisted wire? My mare loves her twisted wire snaffle. The argantines have a snaffle mouthpeice but have nice slpoing shanks that move indipendantly
Here is a link to one.....you can get them with different mouthpeices
Argentine Smooth Snaffle Bit: Saddles Tack Horse Supplies - ChickSaddlery.com
Or maybe a jr. Cow horse bit....i have had lots of success with them as well. Here is a link to one. You can get them with different mouthpeices as well
Cow Horse Gag Snaffle with Twisted Wire: Saddles Tack Horse Supplies - ChickSaddlery.com
I hope this helps
And if you are interested in trying a snaffle again (recommended), here is two that I love!!!!!!
Bob Avila, Avila Training Stables - Avila Training Snaffle Bob Avila O Ring Snaffle Bits (this ist the bit, the bit I use looks just like this only it has a nice curved twisted wire mouthpeice)
Like everyone is saying, start your horse very slow and gradually over time, get faster. You should get her/him correct in all aspects of barrel racing at a walk before you do anything else. I started my mare on barrels (re started) and we are on our 3rd year of training, I still am not letting her run full out until we head for "home"....she just isnt mentally ready yet to take that last step (she over excites herself

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