Hi Pat,
Sorry I missed this post--was involved somewhat in elk hunting too, though not nearly as, uh, LARGE as yours. My wife got picked for an early-season ranch damage cow hunt, so we have been busy off and on in collecting a "heifer" and getting the meat in the freezer.
I just happen to have a bunch of 139 6.5 Scenars on hand, and will run them through the 26 and see what happens. I'm going to buy it from Nosler, partly just to see how long the barrel lasts, since as we all know barrels are like bullets: You use 'em up and replace 'em!