Good response. 20 degree bag wouldn't be great for rocky mtn winters and a slingshot I carry as well at all times, on foot or in my car but it won't keep ya fed like a good bow or rifle and traps will
I use my left over acoustic strings..really i have about 6 of em..all E strings...with the copper coils? and the lil "bead" keeping em from sliding through the string holes..i just use about 20 inches of it? maybe less...thread it through the eye"bead" and rig up my trigger branch and wait
CAUTION: Not really effective it may work but the string will not lock keeping tension to suffocate the animal. Get some picture hanging wire.
Unless you plan on using spring poles. Hopefully gravity will keep the tension. I would not recommend guitar strings.