They handle a gun—any kind of gun—with a minimum of movement. If you watch them at work, there doesn't seem to be much happening.
They are able to shoot fast. They have taken to heart the Gunsite adage that "A good fast shot is better than a slow perfect shot because you're not going to get time for the slow, perfect shot."
They don't jack around with their guns. They accept the fact that if they miss, it's not the gun, it's them.