In the mid 'fifties, I had shot a few rattlers, mostly good head shots. An old timer, somewhere around Needles, California, told me it was not good shooting that did in those rattlers, but the fact that the rattler was striking at the incoming bullet that did him in.
In an attempt to debunk this, I got a friend of mine try to make a rattler strike while I took photos. At a shutter speed of 1/300 second, I caught the rattler in mid-strike, frozen in my photo. At a speed of 1/10,000 second, I could not "freeze" the bullet in flight. That speed was the flash duration of my flash unit. My conclusion was that the rattler couldn't react and strike that fast.