Nice buck, and one heckuva nice shot!
As to the rack, you probably would have mentioned this, but I just have to ask: was he an intact male?
Reason I ask: big-ranch buckaroos will stick a rope on anything they see; the faster it moves and the wilder it is, the more they crave dropping a loop on it... including bear, elk, pigs, antelope, coyotes, pretty girls, their saddle partner's colts, and... deer. Illegal as all get-out, but the young bucks just can't seem to resist the urge to apply a little rawhide-therapy to anything they see.
One of the little side-twists to that irresistible urge to rope is, some guys will castrate a buck before they turn it loose. A neutered buck often grows some pretty wild and weird antlers.
Eastern Oregon = buckaroo country.