That metalic grey snake could have been a Rosy Boa. I have found a number of them in the Deep Creek canyon. Here is a photo at this link of one:
http://www.google.com/imgres?q=rosy+boa&hl=en&sa=X&qscrl=1&nord=1&rlz=1T4DKUS_enUS317US317&biw=1280&bih=546&tbm=isch&prmd=imvns&tbnid=saXpQAynqvT_tM:&imgrefurl=http://www.greglasley.net/nonBirds/rosyboa.html&docid=vRU25soRutj6OM&imgurl=http://www.greglasley.net/images/RO/Rosy%252520Boa%2525200009.jpg&w=725&h=483&ei=QCeaT9LbBOaC2wWp78z0Dg&zoom=1&iact=hc&vpx=691&vpy=2&dur=1203&hovh=183&hovw=275&tx=163&ty=75&sig=117097055643540031776&page=3&tbnh=159&tbnw=209&start=23&ndsp=15&ved=1t:429,r:3,s:23,i:132
Wow, what a web address for just a snake pic :-)