Is their such thing as an automatic sniper rifle?

I have a friend that was a sniper in 'Nam. Snipers only use bolt action weapons because they are more accurate - a full automatic, or even a semi automatic is not what a sniper needs. They also don't need the extra vibration caused by the action of an automatic weapon. Snipers have a saying: "One shot, one kill." - It is a source of great pride among snipers that they ALWAYS kill their target with the first shot! They may go for a heart shot, or they may go for a head shot, but in any case, they don't fire unless they know they have the correct target in their sites and that they will make the kill - even if it's a mile or more away - with the first round. If they aren't sure, they will wait - sometimes for days - until the target is clear.