This is an inert, spent 20 MM projectile round that I picked up at an Air Force target range somewhere in Nevada back in the early 90's, while attending a paintball tournament. I was told that the coloring of the body and tip indicated it was supposed to be an incendiary round. I believe it was a practice dummy round, given the apparently steel body to the round.
If you're a collector, this would be a nice addition to the collection.
$10.00 cash & carry. P/U only, NO shipping.