I disturbed a copper head sleeping under a firewood log last month. It's sleeping for ever now!
We have copperheads out the Wazoo....where I am. So I am pretty much always watching for them.
Generally speaking...I leave them alone unless they are right up around the house or down around my shop area. I keep the lawn mowed short and well away from all buildings but a few still make the venture out of the pasture or wooded areas.
I was trimming some Privet Hedge back away from my shop one time and had one actually advance toward me (very unusual), it gathered itself into an 'S' shape and started feigning strikes my direction from about 4' away.
Normally, I would have just relocated it...but this one I took offense to. Acting all pissy like that.
I had a small chainsaw with me and when the snake refused to crawl away...I revved the saw up and let the snake strike at that. Learned a lesson that day too. IF you decide to use a chainsaw on a snake be certain to use the TOP of the bar! Otherwise the chain will snatch the snake right back around your feet!