Barrels have lands and grooves, not ammunition.
No.
POSSIBLY a rimfire revolver known as the Swiss Mini Gun. It is caliber 2.34mm, or about .092 caliber. It is not available in the US to due laws regarding import of firearms.
.38 Special, yes. Other .38 cartridges (such as the .38 Long Colt or .38 Super), no.
It depends on several factors, but a good rule of thumb is "about a mile."
There are spiral grooves engraved on the inside of a rilfe or pistol barrel. When a bullet is fired, it is forced into those grooves, which impart a spin to the bullet. The grooves are called rifling.
The barrel is straight. However, there are spiral grooves cut on the inside of the barrels. These spiral grooves, called rifling, make the bullet spin when it is fired. Just as a thrown football spins for an accurate throw, the spinning bullet makes for an accurate shot.
When a bullet is fired through a rifled barrel, the lands and grooves of the rifling make marks on the bullet. These marks are called striations, and can be used to match a bullet to the gun that fired it. That DOES include .22 caliber bullets. However, .22LR ammo has a soft lead bullet- if it strikes a hard surface, it may be so badly damaged that the striations are obliterated.
The .40 caliber bullet is a little larger in diameter and is a little heavier (under most circumstances). The .40 will usually have more powder, velocity, and muzzle energy. Also, the .40 is designed for use in a semi-automatic and the .38 is a revolver cartridge.
It's a .30 caliber bullet.
A 22 caliber bullet is 22/100 inches in diameter. A 7.62 mm bullet is 30 caliber or 30/100 inches in diameter there is no such thing as a 7.62 caliber bullet
caliber 38 is a caliber 38. bullet dia. is .357 caliber deals with the dia. or measurement around the bullet head, not the bullet case.
The 380 ACP, also known as the 9mm Short, 9x17, 9mm Browning, 9mm Kurz and 9mm Corto uses a .355 diameter bullet. The 38 special uses a .357 diameter bullet. Additionally, the 380 ACP is designed for a semi-automatic and the .38 special is designed for a revolver.