Fredxx wrote:

I thought read that the term originated with arrows and crossbows. BICBW

OED has that as it's earliest definition,
for a bolt as fastening it has ...

"A stout metal pin with a head, used for holding things fast together.
It may be permanently fixed, secured by riveting or by a nut, as the
bolts of a ship; or movable, passing through a hole, as the bolts of a
shutter."