Here is my journey into Nosler discovery:

http://www.the-gleasons.com/bullets_penetration_tests_for_mu.htm

I have an Omega and it shoots very good groups with the .451 300g Nosler Partition HG bullets and a crushed rib sabot with 100g of 777. The bullet is very strong (will not break apart or fragment), expands very well, giving large wound channel and shoots thru the animal (at least deer). As for the scientific part of this (Sabotloader pointed this out), I pointed out the Nosler benefits ona couple ofotherthread here:

http://www.huntingnet.com/forum/tm.aspx?m=2884930

http://www.huntingnet.com/forum/tm.aspx?m=2883447


Now, SL likes the .458 Nosler Rifle bullets, they are a bit thicker jacketed than the pistol bullets and the pistol bullets are designed to expand at lower velocity, which I think is the right thing for deer, but for elk I would go with SL .458 rifle, since that would be a more solid bullet. I believe SL 300g .458 rifle bullet (a 45/70 bullet) is the way to go in your Omega with either the Orange MMP, the 3 petal EZ or the Crushed Rib sabot.

I do plan on hunting in Colorado for elk myself this year (got my licence plane tickets, car rental etc, ready to go), but I am shooting a Savage in 1st rifle season--my only reason it is my newest gun and I like he Smokeless experience. My bullet is the .458 (again a 45/70 bullet) 300g Barnes Origonal using a Crushed rib sabot. I wanna use the Savage for the extra downrange power, I am shooting about 2400 fps with 67g of 4198. Anyway, the .458 bullets are geat in the Savage, all the .452 bullets are way too loose, and in the Savage too loose means misfire (and I have tried most of the ML bullets). In the Omega, that doesn't happen with 777, but can happen with Blackhorn, since it is very close to Smokeless in terms of ignition.
Best Wishes,
Chap Gleason