The smallest, best known centerfire handgun round is the .25 caliber (or 6.35mm).
The practicality of the .25cal is questionable: you have all of the costs of a centerfire round, with not much more energy than a .22LR rimfire. In fact, nowadays, you are much more likely to find .22LR pistols than a .25cal.
One step up from the .25cal is the .32 caliber. This is just about as out-dated as the .25cal, but there were some very popular weapons in .32 caliber, the Walther PPK (James Bond's weapon of choice) is said to be a .32cal (not a .380ACP).
There are also pistols made to shoot rifle (long gun) rounds. These tend to be smaller caliber than a .25 cal, but are fairly modern (like a pistol designed to fire .17cal HMR).
Centerfire
A handgun. Some European pistols were .32 caliber, and would have been the smallest used, but many .22 caliber rifles were used in training.
22 is a rimfire, 222 is a centerfire.
Don't know if it's made anymore, but it would probably be the .17/44 - a .17 projectile in a necked down .44 Magnum casing.
.22 LR rim fire
43 Spansih
i don't know all the states but Pennsylvania does has to be CENTERFIRE though 22 hornet is one caliber
There are 22 caliber centerfire cartridges such as the .22 Hornet and others, but ordinary 22 cartridges (short, long, long rifle) are rimfire.
Yes, colt makes a few different versions of the 22 caliber handgun such as the Woodsman, and Challenger.
Assuming you mean a bullet fired from a .22 caliber handgun, the answer is, yes, it can, but it depends on several variables.
Can't be answered withou knowing if you are referring to a rimfire or centerfire 22
Xythos