OKAY. Here I go....I'm just going to leave this page up and type little by little since I'm multitasking so I wonder how long it's going to take for this to actually get written?
I feel like I should go from colt to finished here.
First off, every colt is started obviously in a snaffle. Easy to understand. Just a gentle loose ring snaffle. Normally I just start out with a cheap single jointed one, but I am in love with lifesaver/french link snaffles as well. Once the horse is riding in an arena they get their own snaffle on their own headstall.
Next, we heve to evaluate what the horse is going to be doing. Is this colt going to be a barrel racer? Jumping? Dressage? Reining? Cows? Trails? Pleasure?
Me, being mainly a barrel racer now, am almost always riding barrel horses. For that reason when it's time to move up in bits I generally use a Jr. Cowhorse or a Sweet Six. The mouthpiece depends on the horse, I like an iron wrapped lifesaver or a copper roller on a step up bit; no single joints for me on a shank bit, and I find the gag giving that extra poll pressure and a little more warning is good for a lot of colts. I also really like a tender touch, which is by Sharon Camarillo (Same as the Sweet Sixes)
Jr Cow Horse Bits - The Tack Stop Sweet Six - The Tack Stop Tender Touch - The Tack Stop
If the horse is going to be showing in any sort of performance pattern or rail classes (Reining, cowhorse, pleasure, western eq, etc) I use a Billy Allen shank bit. Generally starting with a short shank. The bit allows for lateral flexion because of the joint but eliminates pinching because of the barrel mouthpiece, and doesn't have a port so therefore one less thing for the horse to get used to.
Also, I really love the one with the D rings on the side because it can be used as a snaffle if you need to by switching the rings. If in the middle of the session I need a snaffle, I don't have to change headgear. If I need a little more, I'll find a ported bit later.
Billy Allen Bits
However, even though I do bit up for shows, I do most of all training and schooling in a snaffle still and then maybe once a week or so go up in the bits depending on what they need. Also these are not set in stone. I am willing to try almost any bit to find something that the horse likes. And if they don't like the bit? Fine, we'll go to an S hack or a bitless bridle or something like that.
Little S Hackamore - The Tack Stop
Other bits I have and use frequently:
O Ring Combo Bit
Ring Combination Rope Nose Hackamore - The Tack Stop
Goosetree Simplicity
Simplicity Bit Smooth Snaffle - The Tack Stop
Loomis Gags
Loomis Gag Bit w Browband - The Tack Stop
Josey Tear Drop, and Josey Prime Time. I wanna talk a little about these two. I only use these on VERY strong horses on the barrel pattern in competition; My second choice for a strong horse after the O ring combo, even though I know full well many people on here hate them because of the shanks (Particularly on the prime time) however bear in mind I am not putting these in the hands of a child who is going to pull and pull and yank and whip and spur. I'm holding the reins softly, and when I run the horse I am not going to touch it's face and when I do it's to get the rate and turn for all of .5 seconds and then give him his face again. I find the Josey combo bits to be extremely well made long lasting bits, so any of her combos actually I am not opposed to using. They are not my first choice however. I will also often put a noseband on the Sweet Six or Cowhorse before I go to the Prime Time or Teardrop. It just depends on the situation and how storng the horse actually is.
Josey Tear Drop Bit - The Tack Stop PRIME TIME BIT (aka Silver Million Dollar) - The Tack Stop
And of course I would like to talk a little bit about the Cervi bits too. I find these bits to be very well balanced on a finished horse; I like them as a bit to go up to after the cowhorse and sweet six. I have also actually had a situation or two where the weight of the cervi shanks has quieted a horse. Bailey HATED any lightweight bit (Like the goosetree delight and simplicity, and the lifesaver sweet six) but I put a short shank dogbone twist on her and she quieted right down. I think she enjoyed the weighted feel of the bit. I don't use or own the long shank version of these bits, but they are quite popular right now.
Sherry Cervi Performance Bits at The Tack Stop
One more main barrel bit is actually one I only recently started using. It's a Pozzi lifter. Selena is awful with lifting into the turn just because of the way she's built, but I borrowed this bit from my trainer and it's like a totally differant horse! She lifts like a little pro in it. I'm saving to buy my own but I've been riding in it. I really, really love this bit also because of the
choice of a three piece SMOOTH mouthpiece. Yes, it's true there's a barrel racing bit out there that's a three piece and not twisted!

They come in short, medium, and long shank. The lack of gag and more purchase is what allows the bit for so much lift. A really well made bit, I love it and can't wait to have my own!
PC Brittany Pozzi Collection Lifter Series Long Shank 3 Piece Smooth Bit
As far as these barrel bits go, I use these specific bits but in a variety of mouthpiees depending on the horse. Just something to keep in mind.
Okay so I kinda want to talk about english for a minute which won't take too long. I never rode any horse english with anything but a snaffle in it's mouth. The horse I leased to event in my short-lived dabbling actually enjoyed my barrel horse's lifesaver snaffle, but it wasn't a very english-y look so we switched him to a Myler Comfort snaffle for showing. He was actually the reason I really got involved with Myler. I enjoy the myler system, particularly on my reiners, and still am using that same snaffle on my three year old barrel prospect right now.
I find it very fascinating to see the differance in "acceptance" of bits between western and english. Western riders tend to think of a curb bit and shanks as a way of life, while english riders almost never leave the snaffle (And even when they do it's not a huge step up, such as me using the Prime Time bit)
I'm not saying either way is wrong, I'm just saying it's interesting. I personally love the ability to choose any bit my horse likes for barrels; People don't appreciate how strong a barrel horse can get. Jumpers get incredibly strong too and so can reiners, but barrel horses have the added speed that the other disciplines don't have, which is why I'm glad it's judged only on the clock and not what I'm wearing or my equitation sometimes. I love to show reining and eq and even a little english every now and then but speed is my grand passion, so I choose the bits or bitless options that my horse goes best in.
Learn to use your hands on a horse's face and you can make most any bit kind; I just know I might end up in another bit war.
Excuse typos; Oh, and it took an hour and a half for me to finally get my act together for this little novel. Lol Multitasking and ADHD.