Thanks for your comments, guys. From what you all are thinking, it would look like a no-go from Ruger at this time, and in the current economical climate. I understand that.
But I'll make a couple of observations: 1) If it were strictly a matter of need, we all could get by with one rifle for everything we hunt. I did that many years ago for a long time. I started out, like many Canadians, with a Brit .303, and it would have served for ALL of my game hunting to the present.
The fact that the majority on these types of forums have many/most of the .30-06 case based cartridges, including at least one .30-06 and a .270 or three, proves the point that ANOTHER .458" cartridge isn't needed any more than a .25-06, a .270, a .280, a.30-06, a .35 Whelen, etc. is needed by the same hunter. Or any true Big Bore for that matter.
The % of actual hunters from North America who hunt Africa, for example, is miniscule. In Ontario alone we have an estimated 100,000 moose hunters, and I'd wager that not 10% of them has ever hunted outside Canada. So, another .458 has nothing to do with hunting abroad, as far as I'm personally concerned.
But a relatively short-n-handy .458-caliber, IN A BOLT-ACTION, is very worthwhile to me being a handloader hunting big bears and moose. Yes, I've owned several 1895 Marlins and a few Ruger No.1's in .45-70. And my current No.1 in .45-70 has an extra-long throat and comes very close to the ideal for most of my big game hunting. For one thing, I can use tougher bullets at higher velocity with much better ballistic coefficients.
For moose hunting in Northern Ontario, something that would deal with a big bull in the alders or at 400 yards across a clear-cut would be ideal. I'm talking DIY hunts. A Marlin isn't ideal in any of it's calibers, though they are certainly handy. Then, there are some really big bears in that area due to the fact that they are rarely ever hunted.
Yes, I've read accounts that all you really need is a .270 or .30-06. There are few experienced hunters in this part of the world that travel from Southern Ontario to Northern Ontario (about 1000 miles) to hunt moose (without a pro guide) who actually take a .270 or .30-06. Yes, a few will if they know where they will be hunting and the range will be within a couple of hundred yards, or maybe 300 at most.
But for stopping a big bull moose busting out of the brush at 15 yards in response to a call, they don't want a .277 bullet of 150grs for interrupting a train wreck. Or, on the other hand, for taking on a mature bull -- that can easily go 1100 to 1300 lbs -- on the far side of a clear-cut that's fast departing for another county - or Province! That's why the majority of savvy hunters are toting magnums from 7mm to the .338's, and, still others, even .375's.
Like many of you are thinking, I like to try something new or different. Today, my favorite medium bore is a 9.3 X 62, almost ideal for the conditions described above, especially as I handload it. Going north from here (1600 kms one way), I've taken .45-70's, .300 mags, .338 mags (Win. and Wby.) a .375 H&H and .458 Win Mags. I always take two, one as a backup.
The second observation I make is that, so far, the respondents are mostly from a few western states - Idaho, Montana, Wyoming, etc. And there the traditions are different, though 'Ol Elmer favored Big Bores. Though I've not followed the writings of either Keith or Oconnor that much, I'd be more inclined to Keith's position even though I do use and load "modern" bullets that are supposed to be game changers. I favor Nosler Partitions which are only 70 years old - almost as old as I am - that's ancient!
So, I'd still "like" a short-n-handy Big Bore, like the Rugers in .375 and .416, only in .458" because it could be loaded like "wimpy" factory stuff in .45-70 all the way to a .458 WM, but in a handier package using "modern" bullets. There's a proliferation of .458" bullets that can't be matched by any other Big Bore. I did at one time own a 22" Ruger 77, with tang safety, in .458 WM. It was close to ideal for a .458 in my view. I shot a bear with it @ 70 yards using the 350gr Speer at a little over 2300 fps. Of course, that was a rather mild load which illustrates one of my points.
But thanks for your comments, and keep 'em comin'.
Bob
www.bigbores.ca 
