In Finn's test the 30-06 180 NP out-penetrated the 270 150 and 160 NP, though not by any tremendous amount. Seems fair to assume the 200 NP will at least equal, and likely better the 338 WM 250 NP.

Were I going to AK tomorrow on a Brown Bear hunt I'd likely just take a 30-06 loaded with 200 NP's or a 308 with 180 NP's.

“Perfection is Achieved Not When There Is Nothing More to Add, But When There Is Nothing Left to Take Away” Antoine de Saint-Exupery