Generally speaking, no. You can only fire the caliber for which the gun is chambered. There are some exceptions, but not many.
If you mean a .40 caliber bullet in a .32 caliber gun- no. The bullet would be 8 thousandths of inch too large to fit in the gun. Caliber refers to the diameter of the bullet, so a .40 caliber bullet is ABOUT .40 inches across, and a .32 bullet ABOUT .32 inches across.
The short answer is no. The longer answer is, you might be able to get a .40 caliber cartridge to fire from a .45 caliber gun, but it may damage the gun, and even if it doesn't damage the gun, it will cause other problems. In general (with only a few exceptions) you should never try to fire any cartridge in any gun other than a gun designed for that caliber.
No, the bullet will not seat.
Its the size of the bullet that the gun is made for. its the caliber that a handgun uses
It depends on the caliber of the bullet.
No
No, never attempt to fire ammunition in a weapon it was not designed for!.
Some AUG assault rifles can be modified to be smaller and fire a smaller caliber of bullet, but these are not true submachine guns.
No.
The short answer is no. The longer answer is, it might be possible to get it to fire, but you should never use any ammunition in a gun other than what it was designed to use. It is possible to damage the gun or get hurt yourself.
The word "caliber" refers to the diameter of the internal bore of a gun or firearm barrel.