Yep the 35 Colonel is a great one. Extremely accurate, and kills with authority.
Pac-Nor does good work. I would go 22" and have them duplicate the magnum barrel contour(and flutes) of the Alaskan II, otherwise, you will have some extra play in the barrel channel. The rifle will still be plenty light with that stock/scope/ring combo. Have my buddy Karl @ Kampfeld Custom flute the bolt.
As far as twist goes, a 1-16" will usually shoot everything up to and including 250gr bullets well. I would go no slower than 1-16". Some prefer 1-14", and I believe Griffin & Howe(who invented the cartridge) used to twist theirs mostly 1-12",preferring heavy projectiles.
As far as loads go, I guess you could say I'm old school. 250gr bullets are what define the Whelenator, and have given it it's well deserved reputation. They are the only bullets I have ever bothered to load. Partitions and Hot-Cors mostly.
When you start to handload, look no further than 58-59gr of R-15 under a 250 gr bullet. It is the classic killing recipe for the Whelen, and more extensive load development will not normally be needed........
