buy one or find parts and build it
NO
bullet+metal=gun
No
bullet+metal=gun
Snap caps are by the size of the shell, not the make of the gun.
You can find information on how to make a gun online on Youtube and also at Wikihow. You can learn to make a 22 pistol and also you can even learn how to make a machine gun.
Mainly from the markings on the gun by the maker.
you can't!
It depends on the make and model of the gun.
well it matters what type of gun it is.
You cant exactly make a gun in black ops, but you can customize a gun in multiplayer create a class mode and play online (or offline) with the customized gun.
Depends on what kind of scripts the gun has. Every gun on ROBLOX is unique because players make their own gun they can make you aim through it if they want