The term "86" come from the year 1886 and it means "there is no more..."
In 1886, the US Gold Rush had come to a halt for the common man, or commonly know at "the 49's". By the early 1860s, a single miner could no longer work his claim alone.
Corporation and conglomerates had taken over. Extracting gold via hydraulic mining and destroying the landscape and riverbeds of Northern California.
To '86' something is to render it unusable. The AIEE- American Institute of Electrical Engineers employs the use of a lockout relay that turns the equipment off--Like tripping a breaker (for those who have trouble understanding, imagine blowing a fuse). It turns whatever you're using off, therefore "86-ing" it. It's been in use nationwide since 1928, so it's plausible that the term may have originated from electricians!