Helo Johnny,
What a great find!
I am unsure of what it truly is, but I think you may be correct. Unless it is something left over from a long ago conflict. Eek!
I can not make out what the stamped letters say and maybe that would help.
But, if it were mine and not a valuable artifact, I would encase it in a pineapple knot of beautiful cordage. Or a globe knot.
Then I would put it on the table for everyone to admire. ;-)
SS