I agree about live and let live with respect to snakes, but one time I violated that principle, and more than a few National Park Service regulations, when I was working on a project at Chiricahua National Monument, living in a trailer at an abandoned dude ranch within the monument with my wife and one year old daughter. A very healthy, fat and sleek diamondback showed up one afternoon, and I was merciless. First I wielded my relatively new S&W, featuring my hand loaded snake shot (#8, I believe). Unloaded at close range, my loads did nothing. Out came the shovel, and Mr. Snake got a lesson in long division. A long handled, round point, suitably sharpened, is the ideal tool for this, and many other tasks.

If you absolutely, positively must kill the snake, you will be motivated enough to find plenty of rocks - trust me on this. But the best course is to go your way and let the snake go his.