I'll not argue what is, or isn't a qualified elk rifle.
I will debate the practicality of the .257WbyMag as a viable elk rifle.
Having seen the bullet performance on a number of deer (over 100 that I've shot with both the Roberts and Wby), I will stand by my assement of the 115gr, and 120gr Partitions, and 120gr Swift as being the only suitable factory offerings suitable for elk. And neither ideal, at that. (I haven't tried the any of the Barnes X, TSX, or TTSX or MRX to offer an opinon.)
The Nosler 115gr Ballistic Tip: I've used this from both the .257Roberts at 2,850-3,000fps m/v, and from the .257WbyMag at 3,300fps m/v.
At ranges beyond 150yds, from the "Roberts" it's a "usable" deer bullet. I have gotten complete penetration with a launch speed of 2,850fps. One I shot into a large doe (150lbs) at ~160yds with an angling frontal shot lodged in the paunch, and I didn't attempt to recover.
One deer shot with the 115gr B.T. into the shoulder from the .257wby resulted in a doe that dropped to the shot, and then about 7-10sec. later jumped up and ran off. Attempting to track the deer resulted in an amazing scene of carnage at the impact location. Large amounts of hair and shreds of flesh like what you'd use to make jerky were lying on the ground, and even hanging from limbs of nearby brush and overhanging dogwood tree limb. No blood trail was present, and tracking was not possible due to proliferation of deer tracks (there were at least 3 other does in the group of deer). I located the deer carcass several days later after the coyotes and 'possums had done their thing. The bullet struck the shoulder blade adjacent to the spine and fragmented with no significant damage to the spine. Penetration was perhaps 3" deep at best. There was a 3" diameter hole in the shoulder blade where the bullet impacted.
I've had similar results from the .257Roberts with the 100gr Ballistic Tip under simular field conditions. Ditto the 110gr Hornady InterBond.
Also, I've seen several of the 100gr and lighter bullets from the Roberts fail to completlely penetrate deer, so I can only extrapolate similar performance from the .257Wby. (read -100gr Sierra BTSP, Old discontinued 100gr Nosler Solid-base, 90gr Sierra BTHP, Speer 87gr PtSpt., 75gr Hornady HP)
Since I posted the previous posting, yesterday evening I took my first armadillo with the .257wby. It was a 115yd shot to the mid-spine as he was waddling up a logging road-going away from me (yeah, suprised me too, to see him out and the air temp was 30degF at the time!). Except for some shreds of flesh holding the rear portion of the 'diller, to the front half, the 100gr Hornady PtSpt essentially blew the 'diller in half. About 1/4 of the mid-section of the 'diller was missing! He essentially blew up on impact like a small explosive device exploded in his guts. Much more impressive than a similar hit with a .223, and noticeably more than from a .22-250 w/55gr bullet at similar speed. The bullet remnants dug a 3"wide-8" deep divot in the hard clay traffic pan.
Yes, a patient marksman, and suitable shot placement, with a suitable bullet; the .257wby will take elk. And........ I do the same with a .22cf on our smallish deer.
But...... if I'm spending $$$$ to go to Wyoming or other far distant location to hunt elk, I'm not going to hang my success on being able to pass up on otherwise reasonable shots providing if I'm carrying "enough" gun. I'll take the .338/06 or .338ME, or at the least the 7mm08 and a 140gr Nosler Partition;not to mention the .300RUM or either of the .30/06's with a 180gr or heavier bullet...... or even the .45/70.... I can't see myself going to such distant destinations with either my .30/30 or .35Rem.........though given the oportunity to down an elk with either, I wouldn't hesitate..... given the proper bullets and sufficiently close range.
FWIW: My .257wby Vanguard is wearing a Nikon "Buckmaster" 3x-9x in "cheapo" aluminum rings (Simmons?) on Weaver bases. Seems like a nice match to me.... Works for me. $200 in bases, rings, and scope. Good clarity, focus, and holds zero very well.