As we've already mentioned, one of the biggest differences between pistol and rifle scopes is eye relief. In natural shooting positions, the shooter’s eye is farther away from the scope necessitating the need for more relief. Otherwise, the shooter won't be able to see anything. This is something most rifle scopes do not offer. Rifle scopes also tend to be larger and much heavier. That is why most will not fit on a handgun. Even if they do, the shooter might not be able to see through a scope that's only offering a few inches of relief.