I know saving all copper, pre-1982 US Cents has come up a few times on this forum and I remember a few people saying they did this.
On another forum,
hoardingcopper.com, a member (not me) has posted a video of a machine he built that sorts the copper from the zinc automatically.
I don't know how practical it is, but anyway.
It is in the main forum there, called 'Hoarding Copper Pennies', and the thread is titled something like, Coinsorting video here finally. Sorry, I do not know how to link directly to a specific thread.
Just thought I'd share.