You will haver to define if "biggest" means caliber or overall size.
It depends on whether you mean legally, or what is the biggest handgun available, and whether you mean handgun size, or caliber size. The largest commonly available caliber is .45 ACP, however, .50 AE is also fairly common. That said though, there is also a handgun available in .600 NE. Most states don't have restrictions on caliber, however, some may.
Assuming you mean a bullet fired from a .22 caliber handgun, the answer is, yes, it can, but it depends on several variables.
Yes, colt makes a few different versions of the 22 caliber handgun such as the Woodsman, and Challenger.
There are many handgun rounds that exceed the 44 mag. 454, 460, 500 to name a few.
Its the size of the bullet that the gun is made for. its the caliber that a handgun uses
It should be marked as to caliber on the barrel.
No.
Probably. It would likely refer to a handgun that fires a .45 caliber ACP, or .45 GAP or an older .45 caliber revolver round.
.32 caliber. In a semi auto handgun, probably .32 ACP
45 has the larger projectile. Size of the handgun will vary.
Small handgun