The aoudad is a goat that runs to 250lbs. The do have a reputation of a certain toughness. However, the .257wby is more than up to it.
Personally, I'd use the 115gr Nosler, or 115gr Berger VLD Hunting. These do a "job" on the chest cavity. John Barsness did an article on the Berger VLD's wherein he and others shot a LOT of auodad in New Zealand with the Bergers. They were very, very happy with the results.
For hunting whitetail deer, the 100gr Hornady's have been very, very good. But, may not have enough "umph" to quickly put down the tough goats.
Another pair of bullets that would do the job are the 117gr Sierra and 120gr Speer "Hot-cor".
The .257 was "Roys" favorite. It's one of mine too. Really, the ultimate "bean field" deer rifle.
I normally sight mine in 1" high at 100yds for 200yd zero. If I'm hunting over a long powerline row or airport, ect, I'll raise the rear turret to 2.5" (6 clicks up) for a 300yd zero. At 400yds it's 8" low.
Beyond that range, bullet expansion becomes problematic, as does wind drift.
I've got a .260 that with 129gr bullets is "supposed" to be superior. However, I lost a doe I shot at ~470yds because the bullet for practical purposes didn't expand. I saw the hit through the scope (fur "puffed" at the bullet impact), but found little blood. Coyotes found the deer that night about 1/4mi from where I shot the deer.
(airport using laser range-finder; bi-pod and sand bag).
Let us know how the hunt goes.
I've been told that the "toughest" thing about auodad hunting is dealing with the stench of an old billy if you decide to dress it for consumption....
If you are going to "eat" it, shoot a med. size "kid" or ewe (nanny). Much, much better eating...
