I wouldnt use the sabertooth, I used them one year when i was hunting in Buffalo Park " Rabbit Ears pass" And the first morning i shot at a doe and i found out the hard way that the bullet slipped out of the cup and out the end of my barrel.

385 great plains conical
350 grain TC maxi hunter and or the TC maxiball

Ive found a few posts on the new powerbelt platinums, Most were using i beleive the 338 grain powerbelt platinum and they put the elk right down. Most try shooting 150 grains of powder with them at close ranges and then thats when they run into problems. No more than 90 grains triple 7 with the 338+

I use 225 grain powerbelts in my .45 and puts them right down.

I think CVA also sells a 300 grain Buckslayer conical on their webpage.

What part of colorado you hunting?