Never done them but here is a link to a previous discussion here about making them that might be of interest. I know the NCHFP guidelines for drying them http://nchfp.uga.edu/how/dry/csu_dry_vegetables.pdf say to go "very dry, brittle".

http://forums.gardenweb.com/discussions/1941378/leather-britches-dried-green-beans-blanch?n=18

Dave

Thanks, Dave. I will check out the links. I left this first batch until brittle...about 24 hours in the van with mostly sunny skies. Sure is a lot easier than canning!